I hold some bitcoins and wait for the price rise.
I also use some bitcoins to purchase online goods. The usage of the bitcoin will help the circulation hence adoption of bitcoin. This will increase its price.

Cash is more anonymous than bitcoin. Bitcoin is more traceable than cash. If you are paid salary with bitcoin, then every bitcoin you spend will be traceable by the government. The source of your payment is your employer and the government can find all your spending and verify with the retailers. If you spend the bitcoin on illegal activities, the government will know very soon.

Bitcoin is not the only currency used in on line gambling. You can also pay with credit/debit cards to do on line gambling.
Does it mean you should decline to be paid with your local currency so that you will not do on line gambling?

That is right. If you want to gamble, you have to prepare for the loss.
Gambling is a random process. Some times you win, some times you lose. If you do not think you might lose, you will be upset when you lose.
Gambling could be fun if you are prepared.

It is very difficult to be a professional poker player. Most people cannot live on playing poker. Maybe 1% of poker player can live on that. 1 professional poker player lives on 99 non professional ones.
Not many people can learn the skill to play poker profitably.

Gambling could win us big amount of money. It can also lose us big amount of money. So it is better to play the amount of money you can afford to lose.
There is nothing wrong with gambling itself as long as you can control yourself.
Gambling could be fun.

There are too few retailers accepting bitcoin. Most people do not know bitcoin and retailers are not prepared for that. Maybe in a few years, when bitcoin becomes more popular, it will have some impact. Just not now. So please be patient.

To stay away from gambling, you will not lose a penny. But you will also not winning anything. Gambling is not just about winning. To some people, it is fun to gamble. They enjoy gambling even though they know they will lose.

Give away is very attractive to enticing people to casinos. People will usually spend the free chips and buy more. They will end up losing more than the free chips. They will learn how to gamble in the process. Give away is very effective.

If the amount of money you put on the table is big to you, then reduce the amount. It is better to reduce it to 10% of one day's earning. So if you lose it, it will not affect your quality of life. 

Family and friends can distract the addicted gambler to do something else interesting. They should not lend a penny to the addicted. There is nothing wrong with the gambling itself. It somebody is addicted, it is the problem of the individual. Gambling should be fund, not stressful.

Sorry to hear that. But why would your mother died poor because of you? Are you the sole earner of the family? It is better not to gamble too addicted. Gambling is just a game to have some fun. It cannot earn most people living.

With martingale, you can double (turn) $1 into $2 after many tries. But the winning is just $1. You cannot turn $100 into $200 because there is an upper limit of the stakes you can put on the table and also how many you have originally. If you lose 10 times, you need $100,000 on stake if your initial bet is $100.

The bitcoin is bigger than all the rest digital coins added up. It is still being developed, it will not die soon. If it does die, that is because the community cannot reach consensus on many issues. It will be killed by its users and developers. I hope bitcoin 2.0 will replace it if it dies eventually.

Bitcoin is similar to other properties in the world. It is similar to gold as value storage. Gold can be confiscated by the government and this happened several times in history. Bitcoin is internet money. It cannot be banned without disrupting the internet. internet is universal. 

Gambling will not provide full time jobs for most people. Most of us are not professional gamblers, we do not have the skill to win against the casinos and other professionals. We just gamble for fun. We know we will lose in the long term. The hope of winning keeps us playing.

When the price drops due to the dump of bitcon by retailers, it will attract buyers as the price is low. I would suggest the users of bitcoin to buy back the amount of bitcoin they spend. Circulation of the bitcoin will increase its value and increase adoption.

There will be no block reward in 2140. It could be early than 2140, may be 2100 as the difficulty increases all the time. However, if bitcoin still exists then, there will be transaction fees. Miners will live on transaction fee. The transaction fee will be high enough to support the miners.

Could you please let me join?

It does not matter if the price will go over $400 or not in short term. The volatility of the price matters more than the value of price itself. Many countries use US dollar as a reserve currency, as the value is stable. The normal daily price fluctuation is less than 1%. The normal daily price fluctuation of bitcoin is more than 5%. So retailers will not mark the price of goods in bitcoin, but local currency.