I've been a vegetron since I was ten years old and one of my old mates calls me a "vegetablist" and another refers to me as a "vegetron". Just being silly but I started referring to myself as that because I did find it amusing.
I'm not a militant one though, if anything, being a bloke and a vegetron has led to lots of (mostly light-hearted) grief coming my way any time I'm eating out with friends or colleagues. I can't eat with meat eaters without being grilled (see what I did there?) about all the ins and outs of it, my reasons, my feelings on others eating meat, being asked "what do you eat then?" and such things. I don't even usually tell people but try ordering the veggie option whilst out for a meal and watch the inquisition begin.