I have a feeling that the social context for veganism is extremely different, in a way that can be difficult to imagine, across different social groups (different cities, age cohorts, ethnic groups, social classes, religious backgrounds, etc.).
Most of my friends are well-educated secular urban middle-class 30-year-olds who are somewhat left-wing by U.S. standards. Most of them know dozens of vegetarians and at least several vegans. On average, they seem to view my veganism somewhere on a spectrum from "mildly eccentric" to "extremely admirable".
When I go to other countries, I'm more likely to meet people who are surprised that I'm vegan. Some of them say that they didn't know that that was possible (!) or that they have never met a vegan in person before.
I have also met some vegetarians and vegans, mostly from immigrant families, who said that they had to hide their dietary practices from their families because their families would be so upset about it. (When I went vegetarian 26 years ago, my grandmother expressed a fair amount of concern for my health, although she'd at least met other vegetarians before.)
I think it's easy to generalize from our experience about how other people "normally" react to particular dietary practices, but our experiences with people's reactions (positive, negative, confused, hostile, indifferent, curious) may be a narrow local view.
One time I had a discussion in Latin with a Catholic priest who worked at the Vatican. (I don't speak Italian and he doesn't speak English, so Latin was our best common language.) When he learned that I didn't eat animals, he cited Genesis 9:3 as a reason that vegetarianism was faintly ridiculous. It took me a minute or two to understand that he was absolutely, completely serious.