How do you know someone’s a vegan?
Don’t worry, they’ll tell you within minutes of meeting you for the first time.
[hey, it’s still legal to tell vegan jokes, isn’t it?]
Saw some woman driving around with a sticker on the back of her car that said “VEGAN”.
It wasn’t on the bumper either, but higher up on the paint so that it would be more visible.
It’s not possible for them to keep this information to themselves. It serves no purpose unless others know.