Yes, that's the problem with a lot of these homefeeding ideas. They often don't scale up very well. 10 chickens is easy, 40 is one thing, but when you get up to 100+ things like homegrown feed mixes and cooking things and such start to become a little unwieldy. Hence the popularity of grain-based feed I suppose--it's storable, portable, edible raw. Unfortunately it's often expensive in small quantities and/or not available locally. But the beauty of it is that there's no reason to hew to a "one size fits all" approach. Even on a commercial scale, too. There's no sense to that! It's about being practical and farsighted and figuring out what makes sense according to scale and local region, and finally, unique circumstance, because not everyone is raising fowl for the same reasons or has the same resources. It's as silly to use a backhoe to plant a tomato as it is to use a shovel to dig a swimming pool--if you get my drift...
SO keep the ideas comin'!
Speaking of appropriate feeding methods on the commercial scale, I was unable to follow up on or confirm this but I read in Harvey Ussery's book about a company called Vermont Composting that kept a flock of laying hens fed nothing but what they could find for themselves in and around the giant compost piles, which of course is lots and lots of bugs, mainly. And the company sells the eggs as a side business, at what one assumes must thus be virtually 100% profit. And what tasty eggs they must be! Now there's the sort of clever and resourceful localized approach we'd like to see more of!