It’s a bit obnoxious. I make this excellent chili for family gatherings and nobody ever calls it just “chili”. They always say “vegan chili”.
The other day I made some pumpkin bread. When me and my dad went over to my grandmas house, we brought it. My dad announced “She made some vegan pumpkin bread!”. Grandma knows I am vegan. So of course if I made it, it will be vegan, no need to state that.
I know this is a really stupid pet peeve that will probably get me downvoted to oblivion, but idk. Maybe someone here also gets it.
It’s a form of ‘othering’, which is an attempt to portray something (we don’t associate with) as fundamentally different or alien.
It probably stems from their cognitive dissonance, as in you’re eating cruelty-free and they’re not, so it helps them resolve any mental tension about their cruelty-containing diet by painting yours as strange.
If I were in your shoes, I’d sort out what I make of their behaviour. Are they good-naturedly adjusting to a family member making a lifestyle change or are they trolling. If I felt they were trolling, I’d do the opposite of what they’re doing. I would insist on labelling everything that is naturally vegan, “A vegan [food item, like watermelon]” and correct them each time, etc. To push it a step further, which would likely be too trolling for my tastes, call non-vegan things something like “animal cruelty [food item, like pumpkin break]”
Being vegan - interacting with omnivores and their denialism, projections, etc. - gets much easier with time.
Edit: Another approach would be to non-judgementally ask them about it, which might help them discover their own motivations and feelings around the issue. “I notice you’re prefixing, and I’d like to understand why you feel the need to do that better. Can you tell me a little more about what’s going on for you?”