Ian
Please define a 'small animal" - have no problem if what you are talking about is a mouse!
The scenario you paint may be true of a hungry feral cat, in a 'natural' environment where the only food available is what it catches.
To equate this with the activities of a domestic animal, with its own 'home' with a food bowl and somewhere safe to sleep for its exclusive use is, at best, highly questionable. It is one possible scenario of many.
Furthermore how far a cat (or any predator) travels and how much it hunts are likely to have little relationship with each other.
I might help if you spend some more time watching domestic animals.
David