I'd kind of like to see this in my area- but it's not likely to make me shop at Gamestop anymore than I already do.
One thing Gamestop kind of provides to the games it carries is a sort of price anchoring. If a title is readily available via Gamestop, It typically doesn't go for much more from other sources- because there's no reason to. Why spend $50 on a cart only game from Ebay, with the whole rigmarole of a dispute if it doesn't work, when you could get the same thing for $30 from Gamestop with a 30 day no hassle return? They'll always be things that cost more online, where you can make arguments for condition- but there's only so far you can go out from the Gamestop price before it looks greedy.
I wouldn't mind seeing this effect play out over the retro scene again. It wouldn't effect all games- anything rare enough that it's not always in-stock will still command whatever price the market will bear. It could certainly help with gouging on the common titles though.
