"Yeah, that makes sense," Leon admits, following Bart out into the hall. "I get weird about people coming in to repair the wiring in my apartment - I don't imagine that's less of a thing for people whose wiring is in themselves."

It doesn't occur to Leon that he notably doesn't get weird about people - like Bart - trying to help him out with his injuries, but something about the idea of being a robot and having someone else get in there just sounds more intimate and risky to him. Maybe that's a fallacy, but he's not really thinking about it that hard.