This is an interesting topic, and not to sound crude, but there were times I thought about it, with all the 'free puppies and kitties' ads. These 'pets' are born into a world where there are too many already. Most end up euthanized or being mistreated by owners.
If there were not any stigmas attached to the fact that most of us do own cats and ferrets as pets, using young, unwanted litters as a food source would appear to be a solution.
Let me also say that lots and lots of people keep Rats, Mice, Gerbils, Bunnies and a host of other creatures we typically think of as food for our pets, as their own pets.
I have never tried it, because I know my concious would get the better of me, but for someone else this could be an idea to experiment with.
If I, or anyone else I knew, wanted to give the idea a go, we would most likely be shot down when telling someone, "I'll take your whole litter, they'll be fed to my hungry pythons..." I, of course, wouldn't lie to anyone.
I try to remain open-minded, but this is a very touchy topic. Wild snakes would no doubt eat wild kittens if given the opportunity....