They should always accept pets. Fucking disgusting if they don't
In a way I can understand it. You don't know if the dogs have fleas and will leave same for the next occupants of the room, if they'll mess on the carpet, or if they'll bark while the owners are out and annoy the other rooms in the place.
But in general, we didn't have much disturbance from the pets who were accepted during Katrina. They were well behaved and quiet.
Also, some of the other guests who stay in the hotel can have allergies to cats or dogs and they would be made miserable if they stayed in a room where a pet had recently resided.
A lot of the extended stay hotels like Marriott's Residence Inn accept pets, but charge a $100 pet deposit. I read that the Boulder, Colorado, Residence Inn waived their pet deposits for people who came to stay there because they had been displaced from their homes due to the wildfires. Maybe other hotels should follow suit whenever there are natural disasters.