Well, you could argue that cats keep mice away. Specially wild or semi-wild cats. Not so much relevant now a days, but rats were plague spreaders in the dark

Well, you could argue that cats keep mice away. Specially wild or semi-wild cats. Not so much relevant now a days, but rats were plague spreaders in the dark ages, this is why cats were used to keep them at bay, by having the pet in your domicile and letting it recognise that as its territory, it would protect it, end result being less mice in the house.