A few people will becomes obsessed with any form of fiction that has a huge fan base, especially films. Just look at (for instance) Star Wars, Star Trek, Harry Potter, and the Twilight franchises. In all of these cases, there are a small number of people who take their involvement with the films beyond mere fandom into obsession.
I don't think that's a reason for any rational person to avoid enjoying any of them.
(mind you, there is a different reason to avoid Twilight...it's terrible)
Yes, some people are just going to go overboard over something, whatever it is.