If a guest has a problem with pet allergies, either they make the choice to protect themselves with their medication ahead of time, or choose to meet in a place that is pet free.
I say it is rude that pets would have to banished from a home due to people being allergic, etc.
Most animals can be confined to a room wit the door closed or a cage of some kind if they are less than polite towards guests.
My brother in law is allergic to cat and dog fur. He uses medication, and knows better not to put himself in a situation where his allergies cause him issues. I love cats and dogs but I will not get either type of animal as he would never be able to visit without medicating himself & having his inhaler nearby.