Both cats and dogs show variation in behavior.
My mom's cat Tommy once picked up a tiny field mouse in his mouth, lifting it up by its tail, and carried it around without harming it at all. Granted, we did rescue the mouse before Tommy had a chance to do anything to it, but I'm pretty sure he wouldn't have injured it.
Then again, Patsy, a cat that kind of lives around our house, routinely kills birds and lizards and brings them to my mom as presents.
Rather than dogs being good and cats being evil, it's more that dogs think more like humans (since they're social mammals, like we are) while cats are more alien to us (because they're solitary mammals). But, who are we really to judge animals anyway? Animals don't think moralistically. They just do what they do. Save your labels of 'good' and 'evil' for Mother Teresa and Nazi Germany.
Personally, I find dogs to be obnoxious, smelly, needy, whiny, loud, difficult creatures that need rigorous training and constant care to be bearable (you know, like most of the humans we don't like dealing with). And I can't stand it when they try to lick every square inch of my body; their breath is terrible and I don't want to be covered in their saliva.
Cats, on the other hand, are still smelly but don't smell as strongly as dogs; unless you stick your face in them you can't really tell. They sometimes jump in your lap, but typically just sit there and don't try to lick every square inch of your body. I had a friends cat that would lick the back of my head (apparently he liked the taste of my hair gel) which was certainly a bizarre experience, but I must say I much prefer the sandpaper tongue of a cat to the wet gym sock that most dogs keep in their mouths. Cats also don't require you to walk them for an hour and a half every, single, fucking, day to keep them from pissing and shitting all over your house.
In my book, the only good dog is a dog that belongs to someone else. Dogs are fun, adorable, and can learn clever tricks. Dogs certainly have superior utility to cats, being able to herd sheep, chase off intruders, and hunt other animals. I just don't want to care for any of the needy bastards, and I don't want all my furniture and clothing to be covered in their smelly hair, to be awoken by their incessant barking, and to have to be constantly washing their slobber off my face and hands. I want to be able to fall asleep on my couch without having to wake up every thirty minutes to throw the dog off of me.
And finally, since OP spelled cats with a capital 'C', I originally thought he was referring to the Broadway musical.