I've honestly never come across this mythical self-righteous militant vegan character that everyone seems to know of, and I've a number of friends and family who are vegan and have been for over a decade. My sister and her fella are vegan, I 2 vegan housemates for 3 years when I was in my early 20s. 1 of whom loved the smell of bacon. He just didn't wanna eat it.
I know way more precious omnivores who seem outraged by veganism, your Piers Morgan types pissing the bed over a sausage roll, and whenever anything about veganism crops up on social media they start punching their keyboards with some rudimentary guff about "bUt wE hAvE cAnInE tEeTh". They seem to all have a story about preachy vegans, which I'm sure the majority of are made up.