The couple in front of me was having trouble managing with the deal, so I wound up checking out before they returned to the register. But before they went back to searching for stuff, the clerk said that they could also get a pre-owned accessory. I don't know if that's actually true, but it's something to keep in mind and ask about at your store.
I got some decent stuff tonight, including a copy of Robot Alchemic Drive(!) and a "brand-used" Rallisport Challenge 2 (still totally factory-sealed but marked as Used to help it move out of the store), but I probably will wind up returning most of it if eBay goes my way these coming days. Hopefully there isn't too much hassle with returning parts of this B2G1F deal.