Sportsbooks - Industry Standards, our importance and inflated sense of authority

[Steamtyme]

I've been meaning to address this for several months. I have been reluctant to create this topic myself as I'm not a punter, nor do I enjoy taking on the house. My habits don't really matter here. I also made this in reputation as this is where these issues end up, here or as a scam accusation.

My goal here is to provide clarity for the community, accusers, defendants and activists. There will obviously be some grey areas but I would like a rando to be able to read through this and then have enough understanding to look at a scam accusation, or feedback and have a sense of the nest steps to be taken, or even whether there is any credibility to the claim.

The initiative is to bring together allmost voices who have a vested interest in online crypto positive sportsbooks/casinos. There are a lot out there and new ones popping up each day. The end of 2020 and the start of price action brought a lot of scams and accusations both false and real. This presented a few problems.

- There is very little recourse for a wronged party to go after some of these businesses
- There are a lot of people attempting to take advantage of these businesses - This brings some false positives
- Some of the BTCT community thinks we have authority or power over these businesses
- KYC - as a term is tossed around as if it's a scam in itself, when used as a tool by the businesses
- Failures in writing, reading and understanding the TOS
- Selective scamming is a real possibility
- Lack of information given to the public to protect business "scam" busting techniques

The list below will grow or shrink with input. I would like it to contain any and all standards we know of or can expect when these cases arise. Maybe this will also allow some of these platforms to see possible points of concern that can be removed or addressed in an attempt to improve their PR overall.

Current standards I am aware of

Deposits
- Amounts deposited (less any previous withdrawals) are returned to a "customer" who has been found in violation of TOS.
- Usually subject to certain requirements before being released for withdrawal - AML
- Conversion rate should be known at time of deposit, if converted to FIAT on site


Withdrawals
- Don't be surprised if your no KYC site asks for KYC documents at this stage. The vast majority of these cases have to do with prize size, withdrawal amount and/or timing in relation to deposits. Some times this is KYC as you have been flagged for possible TOS violations. The other side is it can be the beginning of an exit scam and/or selective scamming.
- Received amount should be known beforehand. Including conversion if from FIAT, as well as transaction fees for the network.

Account Investigation
- If they ask for KYC, you have no choice but to provide it.
- A VPN is probably going to result in your account being investigated, and/or could be against TOS.
- I don't know the threshold for being flagged. If flagged for investigation BTCT can't do anything to change that. You still have to comply with their requests.

**Self- moderated to maintain discussion and quality. Any deleted posts will be quoted and moved to a thread yet to be created.

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[icopress]

Withdrawals
- Received amount should be known beforehand. Including conversion if from FIAT, as well as transaction fees for the network.

Very accurately noticed, since mainly transaction fees are covered by customers, the final amount can vary in the 5-10 dollars (depending on which parameters are used 30/50 sat/vB, etc). I'm not sure that in such cases the bookmaker can refer to the TOC, unless the document does not specify the required number of blocks for confirmation in advance [unfinished thought ... ].

[FortuneJack]

Thanks for publicly listing out all the on-going issues that most of the casinos/sportsbooks have.

Our team is more than welcome to discuss each individually as well as listen to the community and note down their feedback.



-
Tornike

[sportsbet.io]

Hi,

Im happy to share some insights from our side for sure. Ill PM them to you in the next few days.

Steve
Sportsbet.io

[tyKiwanuka]

First of all I would distinguish between the different bookie types, i.e. fiat, crypto, hybrid. The more "unregulated" you go, the more likely you are to run into (unjustified) trouble. Why ? Because KYC is the key. If you have nothing to hide and play fair, you will never have any problems in your traditional fiat bookie, because they will KYC you no matter what and after that is completed, they really don't have any strong arguments no more. Same with traditional fiat bookies that added crypto deposit/withdrawal option in the last years. The good bookies will KYC you shortly after registration, I would even recommend to do KYC voluntarily after opening an account.

The crypto books and hybrid books (you deposit crypto, but bet with fiat) don't have a mandatory KYC and that is where all these problems stem from. It's very easy to make multiple accounts and there is a good possibility you don't get caught. This is very attractive for certain people, with a good risk-reward ratio - there is generally more suspicion involved for all accounts/users because of this.

Now the crypto/hybrid books could just say, ok lets make KYC mandatory and we are good. But this doesn't work since it's a) against what crypto stands for and b) they would erase their only USP and lose market shares or not even get them in first place.

There are loads of abusers, cheaters and whatever in this space, so bookies and their fraud departments have no easy job tbh. I believe 90% of scam accusations against somewhat established books are actually just hot air from sore losers or people who were caught abusing and seek for some revenge. The problem is really the other 10%, who suffer under this, get bullied around and have no lobby/help/protection - sometimes even having trouble to get their fairly won money after having completed KYC.

Another issue is that some crypto bookies are really poorly run and there are smart/experienced people taking advantage of this. I started a discussion about something similar last year (The Art of Exploiting vs the Bad Habit of Scamming), where there were very different opinions about whether bookies should just take certain things on the chin and move on. But in the end you often have a user, who thinks he has done nothing wrong (just being smart), while the bookies don't want to take responsibility for their mistake. Who wins ? The bookie; leading to scam accusations, KYC, IP checks and what else. Who is right ? I don't know.

Deposits
- Amounts deposited (less any previous withdrawals) are returned to a "customer" who has been found in violation of TOS.

This is the common practice, but a lot of it is goodwill, to prevent any negative talks and keep a good image. It depends on how severe the violation was, but I personally would be fine, if I didn't get my initial deposit back, if I was willingly and knowingly trying to cheat/abuse a bookie.

Deposits
(...)
- Usually subject to certain requirements before being released for withdrawal - AML

This is fine, but everything more than 1x rollover is not acceptable imo.

Deposits
(...)
- Conversion rate should be known at time of deposit, if converted to FIAT on site

Not sure about this. I personally like, when I tell the bookie how much value in fiat I want to deposit and they then tell me: "Send X.XXXX BTC to this BTC address". Then I will get exactly the fiat value I wanted to deposit.
When I just send crypto to a bookie and let them convert it to fiat afterwards, I have to live with things not being 100% exact. But this shouldn't be a one-way street, where the bookies only ever convert to their advantage (which is hard to track in the end....).

Withdrawals
- Don't be surprised if your no KYC site asks for KYC documents at this stage. The vast majority of these cases have to do with prize size, withdrawal amount and/or timing in relation to deposits. Some times this is KYC as you have been flagged for possible TOS violations. The other side is it can be the beginning of an exit scam and/or selective scamming.

The bolded part is very important and here I blame the bookies for playing unfair. You lose, lose, lose and never get KYCed, you get a bit more lucky and make a small withdrawal, still no KYC. You get very lucky at some point and want to make a bigger withdrawal, suddenly there is KYC and the bullying starts.

I heard stories of users not getting paid, because they were geo-restricted and thus not allowed to play on that site. Their winnings were nullified and deposit was returned. Never ever did I hear about it the other way round, where a user got his lost money back, because he wasn't allowed to play there. They use double standards to their advantage.

Same with other TOS violations. As long as you lose your money, you can violate the TOS at will. You bring them money, so TOS don't matter, until they suddenly matter mysteriously.

Account Investigation
- If they ask for KYC, you have no choice but to provide it.

Yep, thats their most powerful tool. A completed KYC doesn't guarantee you your money though, there are other tools

Account Investigation
(...)
- I don't know the threshold for being flagged. If flagged for investigation BTCT can't do anything to change that. You still have to comply with their requests.

I still think it's a good thing that people can come here and talk directly to bookies representatives; maybe getting support from other members and having kind of objective investigations. It's really hard to fight against unjustified accusations alone and there are few places (if any), where you get help and support.
Bookies are really sitting tight on their money, despite earning good amounts of it. And this is not only meant in a bad way, because your funds are safer in these places with a good risk & fraud department

[NotATether]

- A VPN is probably going to result in your account being investigated, and/or could be against TOS.

Depends on which network the VPN is on. Using a "freemium" VPN (especially the ones that give you a random IP address) or a proxy from a list somewhere? Then there's a good chance that it's also being abused by multiaccounters and blacklisted.

But if it's a paid VPN that lets you choose the location then it's less likely that it is included in the casino's list of "blocked" addresses. I do not think they block entire ASN numbers belonging to collocation IPs unless possibly they have a clause that bans you if you're caught using a VPN.

I'm not advocating for their use I'm just saying that the VPN's IP address you use may not be included in their list of blocked IP addresses which opens up an avenue for more scam accusations because of some casinos apparently not knowing to block these IPs.

And then there's the Tor network which presents another bucket of accountability problems although it can also be classified as a VPN (how will we detect all the Tor nodes and block them? Will we even allow Tor IPs in our TOS? Will we treat an accusation involving Tor IPs the same as one involving VPNs? etc.) the same with private proxies you can host on AWS and Azure and other hosting sites.

[Steamtyme]

I appreciate the engagement and opinions so far. I am just sitting back awaiting more opinions/engagement/discussion before jumping back in. I'll update anything that is sent to me in PM as well if given permission to share.

[spyrosc200]

You can add the ''void of bets on pulp odds'' as an industry standard.

Even though in many cases courts forced bookmakers to pay punters the bets placed with pulp odds, according to industry standards bets on pulp odds are/should be voided. This is how the giants like pinnacle or bet365 still behave with pulp odds so we can still consider void of those bets as ''industry standard''.

However, some books/odds providers have difficulties understanding the difference between pulp and value odds.

Example 1: Barcelona to win against Alaves is wrongly set at 110/1 instead of 1.10/1. While all bookies worldwide had more or less odds set at 1.10, sportsbet or FJ etc set odds incorrectly at 110/1. This is obvious error from the trader and those bets are voided from industry leaders.

Example 2: Barcelona to win against Alaves is set correctly from Sportsbet at 1.10/1 and Alaves double chance is set 6/1. Suddenly, there was a covid outbreak in Barcelona with 25 covid cases and as a result Barcelona was forced to play with U21 team. Market reacted and now Alaves double chance pay1.25/1. This is called value betting and all bets on early odds should be honored.

I think the difference between the above cases are clear.

There is still a 3rd zone, still grey in my eyes. It happened to me in the past.

Example 3: Bet365 opened odds for Berkane at 2.10. It was mispriced. All other smaller bookies/odds provided copied those mispriced odds. So we came to a point whereas whole planet was offering mispriced odds! When asia offered odds on match day, they set odds at 1.05 for Berkane to win and all other bookies followed asia odds. Can we say that odds for Bernake to win set at 2.10 were wrong when whole planet was offering those odds? It is difficult to say.

The example above is a real example, happened to me last year. I personally got paid from 3-4 books and voided from another 2.

https://www.betexplorer.com/soccer/africa/caf-confederations-cup-2019-2020/berkane-fosa-juniors/nXnSnoNt/

After 2 years, i still can't judge if i should be thankful that i got paid from the 3-4 books or be angry that the other 2 books voided my bet.

Worth to mentioned that cases like example 3, are really very very rare, personally can recall only 2-3 such cases in 10 years.

[tyKiwanuka]

There is still a 3rd zone, still grey in my eyes. It happened to me in the past.

Example 3: Bet365 opened odds for Berkane at 2.10. It was mispriced. All other smaller bookies/odds provided copied those mispriced odds. So we came to a point whereas whole planet was offering mispriced odds! When asia offered odds on match day, they set odds at 1.05 for Berkane to win and all other bookies followed asia odds. Can we say that odds for Bernake to win set at 2.10 were wrong when whole planet was offering those odds? It is difficult to say.

(...)

Worth to mentioned that cases like example 3, are really very very rare, personally can recall only 2-3 such cases in 10 years.

Happened a lot to me in the past (in niche sports) and I remember only one time, when my bet was voided and I was furious, because I felt cheated.

I think your example 3 shouldn't get voided, because this is a competition afterall and when you have better information/insights, then you should get rewarded, this is value betting. Especially if the odds stand for a long time until Asia comes out with their odds closer to match day. If you could bet on Berkane around 2-ish for some days, then these are obviously not wrong odds (although for you they are, because you know your stuff), but poor compiling.

A scenario, where I would be fine with getting this voided is, when I bet on Berkane maybe max bet, the market is suspended immediately and is re-opened with 1.05 afterwards. But when you max bet and the odds go from 2.10 -> 2.00, you max bet again and it goes from 2.00 -> 1.85, then these bets must stand.

[PrimeNumber7]

Another point of contention I have seen is that of promotions and (new account) bonuses.

I suspect the above are 'loss leaders' that some crypto sportsbooks use to try to get new customers. When customers are suspected of abusing these promotions and bonuses, sportsbooks will sometimes conduct additional due diligence before allowing withdrawals and may process withdrawals in what some may describe as a questionable way.

[suchmoon]

From a gambler's POV, if the sportsbook takes your deposit and accepts your otherwise valid bet (no cheating, fixing, hacking, "pulp bets" like spyrosc200 mentioned) they should pay out. It simple, fair, relatively easy to enforce, with perhaps some gray area regarding match fixing but at least the major sports should be fine. Any TOS bullshit saying otherwise is predatory and such sites (which is like 99% of them) should be avoided. All of the multiaccounting nonsense shouldn't even exist. If you don't allow multiple accounts, KYC everyone before deposit, or at least KYC before claiming any bonuses or whatever the multiaccounting rule is supposed to prevent. If you don't allow certain countries, KYC before deposit. But of course that would be too expensive, in terms of actual KYC cost and lost revenue, so they let you deposit and play as long as you're losing.

This is a thinly veiled scam and we all go along with it because we can't live without those big flashy sites that offer us odds on SB halftime wardrobe malfunctions. When someone gets fucked over because some third party KYC verification outfit run by two guys and a goat in India rejects their passport we laugh at them here and tell them they should have read the TOS that says the very-respected-never-scammed-site has sole discretion in resolving such disputes and it is very respected so it would never scam. Might even be technically correct, it would just use KYC as an excuse to not pay out because that goes 100% to their bottom line so why not.

Unlike Steamtyme I'm just sick and tired of all this and don't think it will improve. I registered on a state-licensed fiat casino site recently. It's been fantastic. Don't know why I even put up with this pseudo-Bitcoin gambling nonsense until now. Some nostalgia dating back to just-dice and bustabit I guess; sadly that spirit clearly doesn't translate to sports betting. A properly decentralized non-custodial solution could change my mind but I have a feeling if it happens it will be on Ethereum.

[Laudanum]

From a gambler's POV, if the sportsbook takes your deposit and accepts your otherwise valid bet (no cheating, fixing, hacking, "pulp bets" like spyrosc200 mentioned) they should pay out. It simple, fair, relatively easy to enforce, with perhaps some gray area regarding match fixing but at least the major sports should be fine. Any TOS bullshit saying otherwise is predatory and such sites (which is like 99% of them) should be avoided. All of the multiaccounting nonsense shouldn't even exist. If you don't allow multiple accounts, KYC everyone before deposit, or at least KYC before claiming any bonuses or whatever the multiaccounting rule is supposed to prevent. If you don't allow certain countries, KYC before deposit. But of course that would be too expensive, in terms of actual KYC cost and lost revenue, so they let you deposit and play as long as you're losing.

This is a thinly veiled scam and we all go along with it because we can't live without those big flashy sites that offer us odds on SB halftime wardrobe malfunctions. When someone gets fucked over because some third party KYC verification outfit run by two guys and a goat in India rejects their passport we laugh at them here and tell them they should have read the TOS that says the very-respected-never-scammed-site has sole discretion in resolving such disputes and it is very respected so it would never scam. Might even be technically correct, it would just use KYC as an excuse to not pay out because that goes 100% to their bottom line so why not.

Unlike Steamtyme I'm just sick and tired of all this and don't think it will improve. I registered on a state-licensed fiat casino site recently. It's been fantastic. Don't know why I even put up with this pseudo-Bitcoin gambling nonsense until now. Some nostalgia dating back to just-dice and bustabit I guess; sadly that spirit clearly doesn't translate to sports betting. A properly decentralized non-custodial solution could change my mind but I have a feeling if it happens it will be on Ethereum.

This is 100% true. When she talk like this she makes me more horny for her.

Who knows of such a place ? Non custodial is key.

Let's drive the scammers out or force them to be provably fair with no sneaky ways to not payout.
I don't gamble but I want to push all the poor fools that do towards a provably fair systems.

Must be a smart contracts based system by now that has good range and is non custodial.

Where is the merit for her above post??. Usually she spouts nonsense and gets a shit ton?

[spyrosc200]

All arbitrage bets/Sure bets should be honored.

Arbing is a simple but effective strategy that guarantees profits for those who do it correctly.

Arbing involves wagering on all possible outcomes of a game through two or more sportsbooks.

Example: FortuneJack has odds 2.05 for Barcelona to win against Real Madrid
              Sportsbet.io has odds 2.05 for Real Madrid Double Chance against Barcelona

So, if someone bets 100 euros on Barcelona win at 2.05 via FortuneJack and another 100 euros at Real Madrid Double chance at 2.05 at Sportsbet, he will end with 5 euro profit risk free no matter the outcome of the game.

Arbitrage technique can take the form or arbing, sharbing, middling etc. 

Arbitrage opportunities can appear for many reasons: Bookmakers differing in opinion, Bookmakers taking a specific position or running a promotion, Bookmakers slow to move their odds or simply making a mistake etc.

On paper, Sportsbet.io shouldn't have interest if i managed to cover my bet on Barcelona with opposite bet at Fortunejack and vice versa.

In reality though, bookmakers hate arbitrage betting. They hate customers who bet in a way that ensures themselves profits as they know very well that in longterm, they will loose money from such activity.

In recent years, we see many ready to use software in the market that notify the user when an arbitrage opportunity appears among 2 or more bookmakers. Softwares like betburger, betonvalue, rebelbetting etc are very popular among betting community. Many use custom made bots for this purpose as well.

On the other side, bookies have access to those softwares as well. They also have their own tools for that purpose. As a result, they can identify arbitrage bettors after 1-2 bets.

Many bookies have a prohibit term in their TOS that they don't allow arbitrage betting. The problem is that they can't prove if a user is arbitrage bettor or not. In our example, i could have choosen to bet on Barcelona for any reason. I could have choose to cover my bet on another bookie though which is prohibited from TOS.

We many time saw complaints regarding arbitrage betting, when bookie confiscate profits from arbitrage bets etc.

Even though i hate arbing myself, according to industry standards those bets should be honored in full. You will never saw Bet365 confiscating profits due to arbitrage. Pinnacle even welcome arbitrage bettors as they are very sure about their odds/lines.

What options are left for the bookmaker though? It is simple. They honor the arbitrage bets, pay the user his profits and they boot him/limit his account so they cover their asses. All placed bets should be honored though.

[PrimeNumber7]

Who knows of such a place ? Non custodial is key.

I don't think it is possible for a sportsbook to be non-custodial. The outcome of sporting events cannot be cryptographically verified.

[suchmoon]

I don't think it is possible for a sportsbook to be non-custodial. The outcome of sporting events cannot be cryptographically verified.

Non-custodial in this context refers to the custody of the funds, not the resolution. The resolution would still need some sort of oracle and that's fine since we're dealing with events IRL. The problem is the casino holding player funds hostage and instituting bullshit rules on top of the actual bet resolution.

[PrimeNumber7]

I don't think it is possible for a sportsbook to be non-custodial. The outcome of sporting events cannot be cryptographically verified.

Non-custodial in this context refers to the custody of the funds, not the resolution. The resolution would still need some sort of oracle and that's fine since we're dealing with events IRL. The problem is the casino holding player funds hostage and instituting bullshit rules on top of the actual bet resolution.

When you place a bet on the outcome of an event, you are risking money, and the sportsbook might need to pay you if you bet correctly. If the sportsbook has priced the bet correctly, the sportsbook will stand to make money regardless of the outcome because the sum total of the payout will be less than the sum total of the losing bets. Sportsbooks might be risking a small percentage of the total wagers on an event early in the betting, but once betting has been open for a while, they wont stand to lose much on any given bet.

A non-custodial sportsbook would need to put up their own funds on each bet, which would raise the cost of running the sportsbook.

An oracle could still play the same types of games as described in the OP.

[DireWolfM14]

~

Multiple accounts hurt sportsbooks' bottom line, and help gamblers hedge their bets.  This will never change, it's the nature of gambling.  By adding the multi-account restrictions into their ToS sportsbooks are just trying to protect their business interests.  If you're a gambler that wants to hedge-bet why not use two or more different sportsbooks?

There are definitely opportunities for sportsbooks to use KYC to selectively void successful bets, and I'm sure that does happen.  I believe that asking for KYC right off the bat, however is a non-starter.  Most clients won't oblige a sportsbook that requests documents before deposits, and unfortunately it's most likely because they're in violation of one of the sportsbook's terms from the begging.  I'll use myself as an example: I live in a state where online gambling isn't allowed, and my favorite sportsbook doesn't offer it's services in my country.  So to use my favorite sportsbook I have to travel to a neighboring nation.  If they were to ever ask me for my KYC dox, I would have no choice but to disclose that I live in a country where their service isn't offered, and hope that my explanation would suffice.  Of course, if they were to suspect that I used their service while in my home country (through the use of VPN, for example) they would not only be in the right to lock my account, it might be their legal obligation.

There's also the stigma on the industry itself: The gambling industry is probably the second oldest profession in human history, and only slightly less stigmatized than the oldest.  It's understandable, many people find it addicting, and it can be damaging.  So here comes the government, once again claiming to protect us from ourselves.  Being somewhat conservative (small case libertarian) in my political views, I find government intervention more damaging.  I live in a state where they allow a certain ethnic group to build casinos (it really sounds preposterous when I type it out like that,) and there's no lack of them popping up in old cow pastures and on desolate hillsides.  I'm perfectly allowed to throw my paycheck into a slot machine, on a craps game, or a roulette wheel, but I can't (legally) make a much less risky bet by gambling on a football game from my desk.

Sportsbooks aren't run by dumb people, so they must know this.  Which is one of the reasons they often find themselves in disputes with their clients.  It's such a slippery slope; on one hand sportsbooks want to attract as many clients as possible, and on the other hand they want to abide by local laws and protect their interests.

Which brings me to the point of my post:  THIS IS CRYPTO!  I've never considered myself an outlaw, but there have been at least a couple of nanny-state laws at which I've scoffed.  This is the freedom that crypto currency allows us; to do the things that the nanny-state prohibits with their hypocritical efforts to protect us from ourselves.

I hope you're right about some form of blockchain or smart contract technology that help resolve these issues.  But until then, I think we're destined to see online casinos attempt to protect themselves with restrictive Terms of Service, and gamblers will continue to violate them.

[tyKiwanuka]

Multiple accounts hurt sportsbooks' bottom line, and help gamblers hedge their bets.  This will never change, it's the nature of gambling.  By adding the multi-account restrictions into their ToS sportsbooks are just trying to protect their business interests.  If you're a gambler that wants to hedge-bet why not use two or more different sportsbooks?

Hmm, hedging your bets is not what bookies are afraid of or the reason, why they don't allow multi-accounting. (Maybe you meant arbitrage ? Even though that is no problem with multi-accounting as well or would just be a small one). The reasons multi-accounting is not allowed are:

a) Bonus/Promotion abuse
Most bookies offer a bonus for your first deposit. This bonus has some rollover requirement, but is free money in the end. If multi-accounting was allowed, I could just take this bonus gazillion times and meeting the rollover requirement easily by doing the same in another bookie and play opposing bets in markets with low vig all the time, like US sports for example. Bet over in bookie A, bet under in bookie B and I will lose only a few % per bet, while getting my money withdrawable again.
The same goes for some promotions, where the more entries you can make, the higher your chances to win these promotions. 

b) Getting rid of unprofitable players
Winning users/accounts get a personal limit and can only stake very low then. These users only cost the bookie money and thus their accounts are made basically unusable. If multi-accounting would be allowed, these users could just make new accounts over and over, which is of course not wanted.
This is not fair (I think), but it is what it is and as said above a good risk management has its pros as well. The asian bookies have a better approach, since they don't limit these players but just follow their bets, maybe even with better odds and/or higher stakes and thus they are making money even with a generally unprofitable customer. And you can also use (or should I say abuse ?) these winning players to sharpen your odds, i.e. check what they are doing and adjust your odds accordingly.

[DireWolfM14]

Hmm, hedging your bets is not what bookies are afraid of or the reason, why they don't allow multi-accounting. (Maybe you meant arbitrage ? Even though that is no problem with multi-accounting as well or would just be a small one). The reasons multi-accounting is not allowed are:

a) Bonus/Promotion abuse
Most bookies offer a bonus for your first deposit. This bonus has some rollover requirement, but is free money in the end. If multi-accounting was allowed, I could just take this bonus gazillion times and meeting the rollover requirement easily by doing the same in another bookie and play opposing bets in markets with low vig all the time, like US sports for example. Bet over in bookie A, bet under in bookie B and I will lose only a few % per bet, while getting my money withdrawable again.
The same goes for some promotions, where the more entries you can make, the higher your chances to win these promotions. 

b) Getting rid of unprofitable players
Winning users/accounts get a personal limit and can only stake very low then. These users only cost the bookie money and thus their accounts are made basically unusable. If multi-accounting would be allowed, these users could just make new accounts over and over, which is of course not wanted.
This is not fair (I think), but it is what it is and as said above a good risk management has its pros as well. The asian bookies have a better approach, since they don't limit these players but just follow their bets, maybe even with better odds and/or higher stakes and thus they are making money even with a generally unprofitable customer. And you can also use (or should I say abuse ?) these winning players to sharpen your odds, i.e. check what they are doing and adjust your odds accordingly.

Thanks for the correction.  I'm not much of a gambler, so I was aware of these abuses.

[suchmoon]

If you're a gambler that wants to hedge-bet why not use two or more different sportsbooks?

Ah, but that's arbitrage. And probably a violation some sort of "no professional gambling, and we decide if you're a profesional" clause in the TOS. TBH I don't think multiaccounting matters outside of bonus abuse - if you can profitably hedge your bets the site has probably screwed up the odds anyway.

I believe that asking for KYC right off the bat, however is a non-starter.  Most clients won't oblige a sportsbook that requests documents before deposits, and unfortunately it's most likely because they're in violation of one of the sportsbook's terms from the begging.

Great then. No ambiguity at the time of withdrawal. No more pretending that Bitcoin is anything other than a (conveniently irreversible) deposit method for those sites. And perhaps slightly less pretending that they care about their own TOS until the gambler starts winning, if they put a solid effort into actually enforcing those TOS. As it stands now, they're fine with users breaking the rules as long as it's profitable, which is not my idea of fairness.