Yet another point that is often overlooked about livestock, is that most breeds would become extinct if people weren't raising them for meat. Not many people can afford to keep livestock as pets. They have to pay their way, just like people. I can't afford human freeloaders, either. They have to have a job, or be a lot of help around the farm. A pig can't go out and get a job to pay the bills, so we fed them and cared for them, gave them a good life from spring until fall. (winter for the last 2) Then they got slaughtered and ended up in the freezer, feeding us.
Same with chickens and other poultry. I know there are some folks who can afford to keep them as pets, but very few can afford large numbers of them as pets, and pretty much anybody who has poultry or livestock has to figure out what to do with all the extra males. You might keep a hen for eggs, a cow or nanny goat for milk, but the boys...well, no milk, no eggs, no babies to sell or eat...not many folks can afford to just feed them without getting something back. Besides, they start fighting, many become aggressive. Not all female livestock is suitable for breeding, milking, or whatever, either. Some of them are culls. If you don't get rid of culls, you weaken the whole herd/flock. Gotta weed out the less desirable animals, or you'll have an unhealthy herd or flock, pretty quick.
It's either eat them, or at some point kill them to get rid of them, wasting the meat would just be wrong, IMO.
I love the comment about lions vs. vultures and maggots, that's priceless! I plan to use it. Depending on who the person is, I might soften it a little, make it lions and hyenas.
Most of my friends are cool about knowing we kill our own meat. I often take some to potlucks, and they are delighted to eat it. They know they are eating a humanely raised animal, or carefully handled game, in the case of deer or something else. I took raccoon to a pot luck once. Not everybody ate it, but nobody criticized! One of my most citified younger friends, has surprised me in his willingness to try whatever I show up with. He was actually my emotional support the first time I butchered a chicken on my own, thanks to a bluetooth headset, so we could talk while I did the whole thing. That was a huge help to me, he made comments that made me laugh, so I didn't get all freaked out over the actual slaughter part.