Statistically you have more possibility to lose all than earn. But everything is possible because we mention probability and not something of sure. But gambling isn't profitable in long term. Maybe the only game that you can use for earn in long term is poker, I don't see other game that give you this possibility.
Ok, explain this to me. If I play cards with someone else, how come my chances of losing are higher than his? I'd say it's 50% as long as both players have similar experience in the game.