I think all of those are very good questions that we should indeed ask ourselves. In this day and age IS meat necessary for health? In some areas yes, in others no. There is a big difference in eating a factory farmed hamburger, and a tribal hunter killing a wild boar for his family to eat dinner. That leads me to another question, that will make a good thread.
“Factory farms” for cattle are very rare. I live in a major cattle-producing area, (Mo) and I have never seen or heard tell of one.
In Kansas there are some major feed lots, and one could describe those as “factory farms”. But much of your hamburger is never in one, and the cattle that are there spend only a short time there. Most of the beef one eats is grass-fed, out in the fields, though people who are unfamiliar with ranching don’t know it.
I can’t say that meat is necessary for human life in an absolute sense. Clearly, people, being omnivorous like hogs and bears, can live with it or without it. But living without it isn’t so easy. Perhaps more importantly, fully 1/3 of the world’s habitable land is suitable for nothing but grass. We can’t eat grass and live. So, those animals that can eat it and produce very nutritious meat, process the grass for us, and allow more of us to live than would otherwise be the case. 1/3 of the earth’s habitable land is a lot.
I will add that the history of various peoples differs, but most have been at least partially dependent on meat for eons. That’s particularly true of Indo-Europeans, who spent tens of thousands of years as herders on the Eurasian plains where there was almost nothing else to consume but animal products. That’s why most Indo-Europeans retain lactose tolerance into adulthood while most other peoples do not. We adapted our bodies to an animal product-rich diet by (you guessed it) natural selection. Who then, can truly say it’s wrong for us in a physical sense. But moderation is appropriate in everything. Vegans should be grateful to meat eaters. But for the meat eaters, your tofu would probably be beyond your ability to afford it. 1/3 of the habitable world’s surface…remember that.
I have never known a hunter to shoot a deer and not provide for its consumption. One has to ask which is worse for a deer…to be shot down in good health and well-fed, or to be eaten half-alive and half-starved by a mountain lion, coyote or even a feral hog? Deer are subject to some really awful diseases and parasites and are carriers. If not killed by something else, their death from starvation, disease or parasite infestation is horrible. Nature is far more cruel than are any hunters I have ever known.
Animals do not reflect on death. They live from second to second. A mother deer or cow does not grieve the death of her offspring. You can see it in their behavior. Once they realize it’s dead, they utterly ignore it and show not the least sign of sorrow. They will proceed to graze right next to it and wander away in their grazing as if nothing had happened. We humans, however, do reflect on death and on existence, and because we do, we are empathetic. Because we are empathetic, we are prone to transferring our empathy to animals that have no empathy at all themselves or even for themselves. We’re not them, and they’re not us.