It's good only the first times.
But when you realize you're not able to get a real girlfriend and you're still a loser, even if you've sexed many cheap girls from clubs, you feel like you did nothing.
It's not the same for Kaiji. He grabbed the opportunity and tried to do something by himself for himself. He decided to not follow the flow and get cheap money that is asking few efforts.
That's why he's still alive and free after all he survived...