Earlier quoted context omitted.
You know what a key source of protein is in chicken feed? Crab/fish meal. Which is to say leftovers after processing, dried and ground. https://www.feedipedia.org/node/664 At the end of the day, non-pasture food animal raising boils down to getting enough nutrients and time into them to hit your target slaughter weight, subject to feed conversion ratio for the species. Cheaper nutrients = higher margins or lower prod…
Chickens eat worms. Feeding them crab or fish meal is fine. Cows are herbivores. Feeding them meat is abhorrent.
As others are noting, it's the wacky industrial modernity doing its grossly myopic hyper-optimization thing that's the problem (and not just in animal husbandry or agriculture...).