I don't know about JWs as I don't go any more. My JW sister doesn't eat meat but she eats fish.
Where I work it's the custom to bring chocolates, biscuits or cake when it's your birthday or you've been on holiday. This gets harder every year.
Two are gluten free. They won't even eat chocolates unless it says on the box they're gluten free. One can't eat additives of any kind or she goes into anaphylactic shock. She keeps an epipen in her office drawer!
One can't have sugar because she's type one diabetic and she keeps a sugary drink and some sweets in her drawer in case she has a hypo.
We have several vegetarians who can't eat certain sweets because they contain gelatine. Although I'm used to that because my daughter became vegetarian at about age 10, her decision.
We also have one lady who is vegan.
So it's a nightmare trying to bring anything in for people to eat!