Well, I'm not bothered by it.
Some places won't allow RVs that are older than a stated age (the rig, not the driver/passenger!)
Some places won't allow a RVs that are longer than a stated length.
If you won't pay for having your dogs at that RV park, then go somewhere else where they don't charge you. Perhaps you furnish your own bags and pick up after your dog, but I think nearly everyone can attest to having seen pet owners who do not do so. So it falls upon the campground management to pick it up. So if they want to charge for pets, it is their campground and they have every right to do so. And you have every right not to camp there. Problem solved.
