When I'm hosting an event, guest comfort is my highest priority. I'm not a vegan, but if anyone coming to an event that I'm hosting has dietary restrictions, you can bet your ass I'm going to be accommodating.

It's not giving them "special treatment" in my eyes; it's giving them basic respect as my guest. I invited them to an event because they're a friend/colleague/fellow human who I invited to attend. It's my responsibility as host to make sure everyone who decided to join me at the event is fed a good meal.

I'm not vegan, but I sympathize with anyone who has a restrictive diet (for medical reasons or otherwise) so I consider this high on the totem pole of tasks involved in event planning.