I brought it up with a therapist a few times, talked about it as something that gives me happiness and social connection. He was cool with it; he was a wrestling and comic book fan himself, so he understood.

But as the other nonnie said, any good therapist will only be concerned with how your fandom activity affects the issue you're in therapy for. Value judgment shouldn't come into it at all, and if it does, they aren't a very good therapist.