Mine get all table scraps meat included, and including chicken and any roast chicken carcasses that I don't have the time or energy to turn into soup. I know a lot of people wouldn't waste the opportunity, but I don't care much for the broth made from a leftover chicken so the live ones benefit. Chickens don't know what kind of meat they're eating, so people that think it's some kind of cannibalism, but they are definitely clueless, to them it's just protein, not cousin Henrietta. Besides, chickens aren't just omnivores IMO, I think they're practically carnivores and the direct descendants of Velociraptors straight out of Jurassic Park! If they were only a little bigger we could be in serious danger!
Maybe you're confusing the reluctance of people to feed chicken feed that has meat or meat by-products in it. In my case, I prefer to know that the meat I feed my hens come from sources I know about, not from a commercial who knows what kind of ground up stuff source. Also, the feed I've tried that does have meat protein in it made their poo extra stinky so I avoid it mostly for that reason. Maybe it's the meat protein in it, or maybe it's other ingredients in it... regardless, I feed a vegetarian feed (Purina Layena), but not because my chickens are vegetarians. Mostly because my locally owned feed mill carries it and because it seems a more efficient feed for my birds.
