I've been to different vets and it seems that hair on the floor is normal...I've even seen suture's that have been removed still laying on the floor! That was disgusting.
When I go to the vet, I assume there is illness, viruses and other icky's because that is where the sick dogs go. I don't let my dogs sniff and try not to have them in the building any longer than possible. Baby pups are carried in, put on my own towel and carried out. Just like going to an immediate care walk in, I touch nothing and try not to breathe!