But you're not scaling it to the entire population. You're just doing it yourself. I don't see why that step has to be a part of your logic.

Robbing a bank is bad because it hurts people. It's not a very sustainable way to make money, in that (if you want money to buy food, give to charity, buy a bike) you only have to get caught once and it'll be very bad. In contrast, you don't have that risk in a normal job.