I've never met a person who says no vegetarian keeps quiet about it who is able to keep quiet about it, but I still got like 30 years left on Earth to meet one :)
Out of curiosity, is there anything in particular you don't like about people not wanting to eat meat?
Kind of it sounds like maybe you had an unpleasant interaction. Is that your main reason that "they" are obnoxious about not eating meat?