Why are dogs and cats an entirely different issue than nuts? Because wearing an N-95 mask eliminates breathing the dander and hair that induce allergic reactions in some people. And the dogs/cats are (sometimes) providing medical support to people who need that support. Peanuts on the other hand are not in any way a necessity for anyone. Sure peanuts are a good food but the alternatives to peanuts are vast. As I said above, its just a matter of empathy.