Why is it that people that are super into working out have an adversion to overweight people?

Fatphobic,probably project their own fears about their bodies onto others that look like what they might perceive themselves to be and all the negative connotations that come along. The only thing I dislike is feederism or profiting off of an addiction like many feeders feedees do. But I cant hate the feedees as there are usually complex emotional factors behind it. I hate those enabling it