Have you met any Vegans? There is no way they'd accept being lumped into a larger 'Vegetarian' demographic. One thing about Vegans is, is that they are not shy about telling you what they are.
I have met far more people who tell me cliches about vegans than I have vegans who tell me they're vegan.
[0] https://www.thedailybeast.com/vegan-youtube-is-imploding-as-...
Same reaction would occur for any vocal activist caught doing the antithesis of what they preach.
So, if a person has honestly tried everything and they absolutely need to eat some meat and fish to be healthy, then most won't have an issue with it. There will always be crazy internet kooks though.