Why do so many restaurants around the world treat vegans like we have a mental disorder?

I’m getting so tired of restaurants being so rude when it comes to veganism. <br><br>I’m a vegan because I don’t eat meat and dairy, I have nothing against people that do. I can’t stand the term “plant based” because that can still mean you eat meat. I’m vegan because it’s what I choose to do, not because cattle are my friends or because I think livestock farming is bad (I do and I do). It’s not that hard. <br><br>I was in a nice restaurant with friends recently, we asked if they could make a few things vegan, they were very rude. They acted as if we had just landed from mars. Why does this happen so much?