Good exchanges won't make much.
Rogue exchanges and wallet services (which mostly steal) will make tons of money. Even dickhead Mark Karpeles had 500mil USD
![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif)
This is the shit. Bitcoin is the new shit in making money out of thin air.
Coinbase does 50k in transactions a day (what I made up from briefly looking at graph
https://coinbase.com/charts. They hit you when you buy and sell.
What is an average transaction? One BTC - $225000 a day at $450 1 percent? $10 average transaction (highly unlikely) $5000? Then again that 50k is transactions, not buy/sell, but i'd imagine at least half are for buying and selling, as why else would you use coinbase?
I don't know what these exchanges cost to run, but from what I can see opening a legit exchange like coinbase seems to make huge profits, and they deserve to as they are the only legitimate usd exchange in my eyes, so they can get away with 1 percent premium and even more if they really wanted to fuck us.
There is tons of money being made, and to not think so is naive.