There's a lot of MLM/self-help type scams that use Facebook to grow their base that I could see as similarly upset if they were banned or otherwise demonetized.

I suspect that the psychology of an activist making money via legit video monetization is different from a black-hat SEO scammer.

Really though, you can't point to logical reasons for a mass attack against strangers. Someone mentally unstable enough to do that could be triggered by anything.