I think vegans and vegetarians, at least the ones I know, do not lecture you for eating meat. They don't like the fact that an animal was killed so that they could eat. There might be some that lecture, but Ive met many, including my own daughters, vegetarian and pescaterian, who go on their merry way and cook their own foods. I think it's rude for anyone to talk down to them or make fun of what they eat. To each his own.
The only true wisdom is in knowing you know nothing.