This isn't really an answer, but I wonder what would happen if they did stop charging for dogs, soon enough we'd be hearing comments from those who don't have dogs asking why they have to subsidues the dog walking areas and dog waste bins??? they don't just appear from thin air and cost nothing. I'm a dog owner and only started caravaning 2 years ago, before that I'd stay in holiday cottages, they charged even more and didn't provide any facilities, fair enough, our dog stayed on their property, but she never made a mess and we would always leave the cottage as we found it. Truth is no matter what they do or how they charge us for our stay, someone will always complain.