I had chickens growing up. (Which was not THAT long ago...) All we ever fed them was scratch and they were healthy, fat, and laying eggs faster than we could eat them and give them away. That's all anyone I knew then ever fed their chickens. That's all the feed store had for chickens. Back in the days before commercially prepared pelleted rations, chickens were fed wheat and corn that was grown on the farm, and that's about all they were fed, if they wanted anything more, they had to forage for it...and they laid well. Sure, they didn't live ten years, and they were a bit thin...but they were not pets like most people here see their chickens, they were food producing units. Once they were not producing after a couple of years, they were a nice dinner for the family.
Have chickens really changed that much in less than 20 years? Or has the feed just gotten that much worse? Personally, I think the "fact" that chickens have to eat a commercially prepared layer ration to be healthy is propaganda sold by the people who make the feed...same as the people who tell you your dog will not be healthy unless it eats premium brand expensive dog kibble, which coincidentally happens to be made of all the same junk as the regular dog food...From what I read of the label, layer feed is basically corn and scratch ground up into pellets and sprayed with some vitamins and minerals and extra protein from soy. I'd call soy junk food before I'd call scratch junk food. Maybe that's just me. I'm a bit of a rebel.
Layer feed, on the odd occasion it is available here, is $15-$17 or more per bag for crumbles (they never sell pellets) that are mostly dust and a lot ends up wasted. And they only sell chicken feed at our feed store while they are selling chicks, after that, scratch is all they've got. Scratch or corn is $8 a bag. When you are barely scraping together a living for two people on a minimum wage job at 10 hours a week...the price difference is a huge deal. My chickens aren't pets, they're food animals. I treat them as well as I can, but if it costs me $30 a week for a couple of dozen eggs...the price is just too high. So I feed scratch. And let my birds free range and eat leftovers from the kitchen, and I have been giving them some 14% pig feed pellets that I got at a discounted price. They are all fat and healthy looking, I completely cleaned up with them at the fair, won every prize there was for chickens. (I'm having some issues with them not laying but I doubt it is diet because I switched to a high protein diet for several months, nearly went broke doing it, and they still didn't lay...I think it's something going on with the birds, I know dozens of people whose birds are not laying no matter what they do!)