Vegan fundamentalists.

Veganism is a perfectly cromulent diet choice as long as you take care to supplement any vitamins and aminoacids your diet may lack and you don’t force it on growing children or obligate carnivore pets.

The problem with the mods in .world’s vegan community, is that they don’t treat it as a personal diet choice, but as a cult. And their view of “heretics” seems directly inspired by Warhammer 40,000.