Okay, so let's say that instead of the hunting down what's left of HYDRA-route, Bucky turns the other way. He's so horrified of the things he's been made to do that he swears never to touch a weapon again, never to hurt anyone,... you get the idea.

He's also too ashamed to turn up at Steve's doorstep. Stealing (food, money, papers, ...) is out of the question too, so how's he gonna get by? Prostitution, obviously.