The first point is that for many, being vegan isn't a "dietary restriction", but a lifestyle based on a moral philosophy that we shouldn't harm sentient beings

The first point is that for many, being vegan isn't a "dietary restriction", but a lifestyle based on a moral philosophy that we shouldn't harm sentient beings more than necessary. Eg, the Vegan Society's definition is (in part): "A philosophy and way of living which seeks to exclude—as far as is possible and practicable—all forms of exploitation of, and cruelty to, animals for food, clothing or any other purpose." There are vegans who really get into being VEGAN as an identity. Then there are the other ones who just do what we do and don't see a need to volunteer it or announce it at every possible chance. Some just live their lives, some participate in various aspects of animal rights activism. Either way, the VEGAN identity folks tend to be the ones that you will notice and remember. The rest, you pass by every day and probably never even know. (It's also worth mentioning that there are also a lot of people who are "vegan" as a fad diet (like "keto" or "paleo") but don't subscribe to the philosophy (vegans will usually try to make the distinction that those folks really just follow a plant-based diet), there are vegans who also get into weird things like raw food, alkaline water, fasting, etc. Like it or not, any large group of people will have fringes like this and they tend to be very vocal and attention seeking.) Similarly, there are meat eaters who make BACON a huge part of their identity and like to remind you every chance they get how much they like it and "carnivore" dieters, etc.