Cats, like any other predators, are born to kill other animals. It’s a natural order of things. My cat regularly brings back mice, birds, lizards and little snakes. I do have to get rid of them, but he makes me proud.
Natural, in the same sense that air conditioning and pickup trucks are natural.
Feral cats mostly live in cities, or are fed by farmers to encourage them to stay where they can protect feed stores. Like modern corn (maize), they don't naturalize into the wild.