I mean even my own currently-alive ancestors (farmers, the majority of them) don't look at livestock as living, conscious beings. They obviously care for each animal and give them a swift and as-painless-as-possible butchering when the time comes, but they're not the bleeding hearts that many people these days are, they're mostly just vehicles for vital necessities.

I don't find it difficult to imagine my great-great-great-great-(fill in the appropriate number of greats here to qualify for ancient ancestors) grandmother butchering a pig and not really giving it a second thought at all, having grown up on a farm myself. Hell, my current grandma is probably much gentler and gives the pork a much better time than my ancient ancestors did