I am a recovering alcoholic and vegan. I have worked for a startup with a bar, or as one guy would always introduce it to visiting guests “our pride and joy”…not always to guests who would be receptive to such a comment.
I was never harassed for either at that startup, but I wasn’t always happy busting my ass during crazy long stretches while others sat at the bar and drank. Still my choices were respected there, and some of the employees even followed my example by doing stretches of veganism and sobriety, though their motivation was to lose weight.
I am now at a company where my choices are very much respected, as am I. My boss makes jokes about tofu with me, as he does about me being a Cubs fan, but never disrespectfully. He never says a negative word about my sobriety and always ensures that I feel comfortable at business dinners, as do all others I work with. We do have “beer cart Fridays” every other Friday, but the “beer carts” also have wine, margaritas, and nice local sodas; the sodas always run out first. :)
There are those who will respect you (and thus your choices), and there are jerks. Why they choose to act like jerks can be for many reasons, but at the end of the day they make that choice for whatever the reason, and that is not your issue or concern.
Find a place where you are respected, working with, and for, mature people; perhaps this is your own company. Maybe ping Brad Feld to see if he can point you in the right direction. But take care of yourself by putting yourself in a healthy place.