Spots are an attractive feature on a dog. A dog is better protection from intruders. Dogs enjoy ball games. But they don't spend six hours on the phone trying to get tickets for France 98. Dogs greet each other by sniffing bottoms.
Men are far less polite.
Puppy love doesn't wear off so quickly with a dog. You can be prosecuted for neglecting a dog. Dogs can find their way back home - even after a really heavy night out. Dogs can be trained not to lie on the bed. Men always lie in bed.