When prices were high, and everyone announced that end users would just switch to nonconventional alternatives, with very little detail about what they were, I tried to figure out where these feed supplies were going before?  I assume this is all byproducts of other agricultural products still grown on a farm, not some super new synthetic feed straight out of the local oil refinery?(rhetorical question)  
So before they found their way into the feedbunk, were all of these apparently nutritious byproducts composted, incinerated, landfilled, or flushed down the drain?   And now that corn is affordable again, and apparently demand is back with a vengeance, what is the fate of all of these byproducts now?  What does that do for overall demand, and for the profit margins of the processors?

Sorry for the oversimplification, I'll leave the details to someone who knows more than I about this.