I have been pet-free for three years. Before that, I had always had at least one cat. Sometimes, more than one. Cats are really good pets for people who don't always want a pet. They are affectionate when you want them to be and when those times come when you don't want to be bothered, they are happy to oblige. As far as a cat is concerned, people only exist to open cans. Yeah, once in a while a person can scratch a cat's head, but they are primarily a can opener.
Dogs, on the other hand, are honest-to-goodness, high-maintenance pets. Dogs need to be walked and played with and, because they love to roll around in their own shit, they need to be bathed. (Cats take care of that on their own, without human assistance.)
Dog owners are high-maintenance, too. Dog owners treat their dogs like most humans treat their children (the ones that they love, anyway). And because dog owners love their dogs, everyone must love their dogs. You must! How could you not?
I have lost track of how many times I have been accosted by a dog on the sidewalk — all muddy and slobbery and smelly — only to have its owner assure me that "He's friendly!" or "He won't bite!". Well, I don't want to be friends with your fucking dog. I have visited dog-owner friends who refused to pull their over-curious canine away from me, while laughing and explaining, "He probably smells your cat on you." Well. I smell his excrement on him, so please get him the fuck off of me. I don't love your dog. Only you love your dog.
My wife had a few dogs growing up and has brought up the subject infrequently in the twenty-eight years we have known each other. Fairly late one evening, my wife and I were driving home in a treacherously heavy rainstorm. A block or so from our house, I could make out a figure in the downpour. It was a man dressed in a rain slicker with a waterlogged hat drooping on his head. In one hand, he held an open umbrella. In the other, he gripped a leash. At the end of that leash was a soaked dog, its sodden fur matted against its body. The man dutifully followed the dog as he slowly and deliberately sniffed the ground looking for a place to crap — or possibly for nothing in particular. I pointed out the fogged window of our car to the sorry-looking sap with the dog and I said to my wife, "Y'know why we don't have a dog? Because if we did, that poor asshole would be me."