I think there are a few keys to this. One is the feeling of superiority. Knowing what other people don't know. Some people just love to feel superior to others.
Also there is the delusion of thinking there is some sort of control over everything that happens. I heard people giving off comments about the attack in Paris being a "hoax" after only an hour when no official story on it had even come out. Maybe it's a feeling of security knowing there is a secret meaning behind all of this stuff and there aren't crazy people who would just go out and murder people.