Well, I wouldn’t say vegans are common anywhere (where I’ve lived). It’s like 1-2% of the population.
And while my point indeed was totally anecdotal, it goes beyond just knowing people. There are other hints. I still often visit family in my childhood home area and even today you can notice a different in marketing. Restaurants there often don’t even mark meals as vegan on the menu, while restaurants in big cities often have an entire section for vegan meals.
Also supermarkets specialising on bio food and such (our equivilant of like wholefoods) aren’t present at all. You’d have to drive like 30km to get to one. Also in regular supermarkets meat replacement options are either not availible or poorly stocked.
So I’m not sure if it’s a result or a cause, but I’d say it’s much harder to be vegan in a rural area, just from a logistical standpoint. And you get a lot more local farmers markets, so you also have access to fresh and relativly cheap meat.
I’ve tried to search for some statistics about the distribution of vegans in urban and rural areas, but didn’t find anything useful. I did find some quora and reddit threads with quite a few replies of people that have similar expirences to mine.