Well, sometimes your aunt offers you a free cat, and you're like, hey, why not, it's free! and it's still a kitten and it's cute and your girlfriend/later wife loves it. Then the cat runs around maniacally and you're like hey, that cat needs a friend. So you get another cat! It's a feral little barn kitten that came with fleas and ear mites, but it was 'free' too, and it does it's job of making the first cat behave better. So you keep feeding it.
Then your sister in law says, hey, I've got this stray dog I can't keep because of my MS. But I love it and I want her to go to a good home. So then you get a dog, too, because you like your sister in law and don't mind dogs.
So, there you are, two cats and a dog later. And they're good friends and good pets, and no internet crank is going to make you see the error of your ways, because the pets are furry and happy to see you.
What was I saying? Oh, yeah, Merry Christmas!