Gambling only because a problem of addiction if one allows it to be. It's almost the same with how other forms of addiction work so that's why I agree that even constant winnings can contribute indirectly to the addiction. One mentality that fuels gambling a lot is the fact that in gambling, you can only lose 100% of your money but you can win as much as 1000x worth of profit.

If you do it long enough to convince your brain that it's a need must situation, then it becomes an addiction.