I’m inclined to say “upbringing” but maybe there is a social/classist reason as well. Traditionally, tribal people have depending for the bulk of substance on gathering (as opposed to hunting, as you know) that included insects, toads, and other sources of protein. But, as we became less nomadic, we developed husbandry. It made sense. But, I think meat has always been a premium that the poor had less access to. Aristocracy favored corpulent women (to an extent) because it showed wealth. Peasants ate gruel. Hunting the king’s venison came with stiff penalties… Granted, I think there should be a premium on “life” that is sacrificed for our survival. But it also has to be balanced with health. I don’t eat meat every day, but I am anemic and the time I tried (with all the spinach and soy I could handle) to be entirely vegetarian, I couldn’t manage. But even if we all went down to three days a week having animal protein, it would be an improvement. Or small portions of it.
Sadly, it’s now more expensive to be pescatarian, vegetarian or eat cage-free free-range meat.