I've only been to the auction in detroit a couple of times, and the only thing that brought me there was pre-arranged sales of fish I'd been looking for, while i was there I put several items up for priority, won some of them, drove the price up on some others. but without the presale of fish I wouldn't have gone at all. So, yeah, it makes no sense to me that they don't allow presales. I get that a guy pulling in opening a van and selling fish at random would deter from the auction sales but pre-arranged sales mean you're for sure getting people there.