Why does the UFO subject attract so many trolls?

I don’t believe in pixes. But I don’t get angry with people who do, nor do I go to pixie communities and ridicule and attack them.

I’m curious what it is about the UFO topic in particular that attracts people who steadfastly claim UFOs are nonsense, get angry about it and attack people who are interested in it? Why do people who’s post history indicates they only ever ridicule the subject spend so much time in this and other UFO subreddits? What’s their motivation, and in particular why do they get so angry about the subject directed at people who do believe? Why do they care so much about something they believe is ridiculous?