Namsnanny I am not, as you may have surmised, a cat lover. However, my DC have cats and I can tolerate them, and can see the appeal of kittens so I do get distressed when I see cruelty towards cats.
However, when my family tell me that one of the cats has dismembered yet another blue tit, brought in a blackbird, that upsets me very much too. Then I worry they may have brought in a mouse and I'm going to see one peeping at me from behind the corner of the bathroom (well, not at the moment as I can't visit).
We had a neighbour whose cats used to dig up my large planters at the front, thank goodness she moved.
I don't think that worms have the same parental caring instincts as birds, Loislovesstewie. They lay eggs and then leave their progeny to their own devices, unlike birds.
Domestic cats are fed and do not need to hunt and kill prey whereas birds need to catch worms, insects and find food for themselves and their offspring even if people do provide them with some seeds etc.
Grey squirrels are vermin but they are very entertaining.