It is not wrong.If you know how to gamble.natural greed from people makes it wrong.
Greed if you see your winnings growing and want some more. Gambling owners only gives you a the table and the game. But they don't give you that greediness and that mind set that if you lose you will come back to get it back.
Yup is actually your self is not the other people.
That is why you need to control yourself if you are losing your money or winning.
You need to know when to stop, because if you don't you can't never tell how much you will lose later.