Anytime anyone uses the excuse of 'I'm an X' to qualify whatever unintelligent, bigoted, nigh-defenseless garbage they just spewed as ok, since they have the magical shield of 'you must respect what I say because my beliefs are sacrosanct'
Tied to that, people who believe, in any religion or philosophy, that being happiness is obtained through self-denial, and the denial of others happiness and freedoms. Whatever your beliefs, humans have a rational, intelligent mind. Happiness is the goal of life right along reproduction, as it makes us live longer. So what's the point in denying all the different forms of happiness? When these folks get on the internet, they always make me rage.