I was already aware of it, saw it last night.
Sounds like he's upset at how the market works: some people value being able to travel with their dogs, and hotels respond to that preference.
(b) One can acknowledge that dogs are allowed and still complain about things that annoy you about their presence. That’s not a hard concept.
You know what else is not a hard concept? That it's silly to complain about things that annoy you when you choose to put yourself in a situation where those things that annoy you are explicitly allowed.
But telling him that the dogs are, in fact, allowed to be there isn’t relevant if the point is that we shouldn’t even be accommodating dogs to this extent (by allowing them in our hotels).
Except there are places where they are not allowed. I'm pointing out that the solution to his problem is "stay at those places instead".