I don't think it's as physiologically screwy as some make it out to be. Work on the blue zones indicates a relatively low amount of meat consumption in the longest living societies. It also shows a high level of low intensity activity, low stress, sense of community etc. Just not eating meat, or much of it, doesn't equal long life. Looks to be a package deal.
Either way, go to Mike Mahler's website and look into what he's got on veganism.
He's strong with KBs, pretty strong with barbells and doesn't ingest any animal products.
Aggressive Strength or something like that is the name of his E-Mag.
Ethics is a personal judgement. I feel that raising animals for meat is unethical.
Don't raise it then. Learn to shoot, or learn to use a bow, and get a hunting license. Or learn to fish. Or don't.