If Jay's estimates are relatively accurate then the collation must be poor, or where are they all? I guess the only other explanation is that we over-estimate the amount forum members bought, and there are others buying them that we will never see.
I think that a lot of non-forum-member card collectors bought Old School, and many were probably quite content with whatever sketches they pulled. I only found Greg's forum 4 years ago, but I was always an active and avid Wacky collector, as well as a non-sport card collector, and even if I wasn't aware of the forum when the set was released, the ads in NSU would have had me buying Old School like crazy, just like I've been doing! But, I wouldn't have been reporting anything here. And, if you're a non-sports card collector who just wanted a few base sets and sketches, you might not be inclined to ebay anything you don't have doubles of, particularly if you don't check ebay every day to follow prices.
I haven't sold anything on ebay in years. Without the forum for trading opportunities, even the sketches I had doubles of would likely still be in my collection.