Ive been reading this thread and it’s made me think... so for what it’s worth (pretty much what you paid lol), my musings:
The color in the yolks probably actually is at least slightly healthier. The pigments are themselves often antioxidants and/or characteristic of vitamins or vitamin precursors (which become the vitamin in your body if your body needs and is calling for that vitamin.) I’m just extrapolating from general knowledge, but I would be surprised if I was wrong about this one.
As to the bagged foods... (excluding small manufacturers who may be free to be more dedicated to quality)... On the one hand the manufacturer is in the business to make money and also has an obligation to stockholders to turn the highest profits possible. OTOH, if their food isn’t of reasonable quality and flocks noticeably suffer, they’ll lose customers and market share and the stockholders will move on to fairer horizons. Just because “studies show” their foods are the best option for feeding poultry doesn’t mean we should take those studies uncritically as gospel truth.
Birds in the wild live shorter lives because of predators, scarcity, stress, predators, disease, predators... not necessarily simply because they lack manufactured feed. Our chickens are descended from long lines of chickens who lived productive lives mostly on whatever the family had left over from the table and the fields, and on their own free ranging.
A couple of problems with manufactured feeds... first, they typically contain corn and soy. So far not so bad, but soy and corn are big GMO products, altered so that they can survive large, repeated applications of glycosides (aka “Round-Up Ready” varieties). These herbicides are very durable in the environment and in the edible (and other) parts of the treated crops. Glycosides are (in addition to acting as antibiotics) extremely toxic, but not in an acute way... rather, in a chronic, accumulative way (like nicotine). Second, even though you pay for organic, non-GMO, you can’t know (nor even can the manufacturer truly know) that what is in that bag is really organic, non-GMO.
Bottom line, if it’s an option at all, I give my girls table scraps (including meats), hay and fresh veggies. I’m still feeding manufactured feed, but the goal is to find a way to cut it down as much as possible. Come summer, they’ll be on pasture, and I think/hope that’ll help a lot.