Of course gambling is wrong. It's nothing but a good way to lose lots of money. The idea of gambling differ from one person to the next. The two possibilities I see are...
A.) To have fun.
B.) To make money.
Having fun while gambling isn't an issue I have with it. I think that should be the idea of gambling. Having a bit of competition or enjoyment of betting a little money. Using it as a way to make money, however, I feel is "wrong".
Its supposed to be fun right.. until you lose.
Thats where most emotions boil up, and make you explode which determines the level of the individuals self control lol. And most people I know just "rage bet" afterwards since they already lost something, they say the "fuck it" mentality.
eg: $20 loss turns to $100