I'd think that is part confirmation bias, and part just where you work. You're in one of the soft sciences, right? Particularly one that deals with groups that would fall further onto the left of the political spectrum?
If so, I'd expect that you would have a higher percentage simply due to those two factors.
Also, considering the influence of Indian culture in the UK and their leanings towards veganism/vegetarianism, I would again expect that it would be easier to find vegan places over there than it would be here.