Those are likely sell at the market orders.You can try to sell at the market and the MM may give a sale out to 5 digits.They can do that,but we are restricted to 4 digits.You'll likely get about 10-20% of .0001.The MMs will make money on those even after a reverse split.
Probably acounts for some of the volume.I can't imagine who would buy this crap at this point.