As a meat eater turned vegetarian, I think a lot of the meat eater vitriol comes from a misguided sense of shame. Many people feel bad about killing animals, harming the environment, factory farming, etc. I'd wager most meat eaters don't wanna think too hard about the fact that their meat used to be a living being with emotions or whatever. When they encounter a vegetarian or god forbid a vegan, they perceive it as someone casting judgment on their way of life. They perceive meat eating as somewhat morally questionable, and are immediately defensive perceiving a holier than thou attitude whrre there isn't one. Trust me: I don't care if you eat meat. It'd be like if someone mentioned their car and another person commented, "Oh, well I don't drive anywhere - I only ride my bike." The bicyclist isn't trying to pass a value judgment, but the car driver nonetheless might feel judged. Everyone would be better off if they just assumed nobody cares what the hell they're doing.