my poullets just get their grower crumbles and scratch, and every once-in-a while i'll throw grass clippings in there, and thats all they get, and bread sometimes. as for my layers, they get everything, grass, bugs, breads, table scraps, anything but chocolate and citrus fruits and raw potato peels. i have given mine avacado a few times and they love it, i don't see nothing wrong with one every now and again.
there are MANY MANY members that feed the chickens own eggs back to them and chicken carcuses and every other meat for that matter.. meat is good for them... protein..... chickens are omnivores
ETA: I didnt start feeding scraps till they were laying