Toured the San Jaquan valley (spelling), on a farm tour once. They were feeding byproducts there I never dreamt possible. At that time, there was a large vegetable industry there, but that was 30 years ago. Things that I would have thought were poisonous were being fed.I know a guy who had a smallish feedlot that was located in between a green bean processing plant and a place that makes taco shells. Packed a silage pit full of bean waste and had a truck load of cull taco shells nearly daily. The area grows a lot of grass seed too. So he would get grass seed straw cheap. He fed a TMR of green bean silage, broken taco shells, and grass straw. All which he got for free or nearly free. It also helped that he is a buyer for a cow kill plant so he is at the sale several days a week. It was a small gold mine but..... a divorce took care of the gold mine.