To answer your very interesting question:
I am 56, I have been an ova-lacto vegetarian for 36 years.
(I eat animal-friendly dairy and eggs, nothing that takes the life of, or is derived from, an animal). I am a culinary historian and have included aspects of this topic in my books.
1. I live in a rural mountain-resort area of Southern Calif. The geography did not influence my choice to become a veggie. In fact, this area is slow in food trends, so in the early years of being a veggie, I spent a lot of time reading labels and never going for fast food.
2. No person in my family was (or is) a veggie. In fact, I come from very old planter families out of the South (all the way back to Virginia of the 1600s) and my parents owned a fine dinner house... I grew up in the kitchen, at home and in the restaurant. My husband is not a veggie, nor are our three grown sons. I cooked many double meals for us, because I wanted each son to make his own choice. Yes, I cook meat, for those who eat it. Food is hospitality and for a meat eater that means they should have what makes them feel welcomed. This is a philosophy that is very personal and influenced from having grown up in a restaurant family. Food is culture and how it is gathered, prepared and offered is an indication of hospitality. I believe that individual choices should be respected.
3. Twenty years from now I will still be a veggie, it is a commitment to a lifestyle that is compatible with my personality. And one other thing... this is not a religious issue, I am the only veggie, Episcopalian at my church., and because of the open and accepting nature of the Episcopal parish...this is never a problem.