Read the book “Wolves in Russia”. Enlightening and a bit frightening. Wolves kill just to kill. The gentle term for it is “surplus killing”.
Gunner
I’m going to go out on a limb and say predators in general do that. I’m not defending it, but it’s probably how they keep their skills sharp and teach the younger members of the pack to hunt. But watch cats, and heck, my dog loves to kill lizards. So it should come as no surprise. Predators kill things, and not just enough to eat.