I don't know why you are so convinced that guys didn't 'sell the manure out of $8 corn'.  I sure did, the only reason I didn't sell more is because I didn't grow more....  I know of a couple cases where guys may not have swept their bins out, but that would be because they just plain didn't need the money.  Pretty hard to second-guess the decisions of somebody who has made enough good decisions to reach that point.