Argue against keeping cats and accuse their owners of harming and killing animals.
Do you even read the label on your cat's food? How many animals did you pay others to kill for you, just this year alone? How many animals did your cats, and those cats that you support being outdoors, torture to death just so you can say, "Awwwww... such a good hunter you are! That's a good kitty!" The only result of which was to make their own self feel good, no other reason. You're not only sad, you're pathetic.