The truth is that this life is so bias that we tend to attribute some negative only to the poor and those that couldn't make good out of something.
It will be really hard to call a successful gambler an addict, okay let's look at some of the characteristics of an addict. They tend to bet compulsively, poor management, always on their gambling account, the urge to gamble is always there, they can resort to using money that's not theirs to gamble.
But for a successful gambler you won't see any of those characteristics in them, they don't gamble anyhow since they have to take their time to analyze before placing a bet and if they are unable to figure out a good probability for their winnings they can just leave the game till another time. Although not everyone behaves the same way so among those that became successful through some lucky bets you'll be able to see adducts among them.