It sounds great on paper, but if we put practicality to it, it just means people are gonna get very little for something that they can probably sell to a collector for a lot of money. Which means the only people trading in things are desperate individuals or people who don't know a thing about gaming. Or ebay.
Frankly, if I wanted to find retro games, there are PLENTY of places that I can go to. Most of which offer WAY better values of used products than GameStop does.
Not to mention, whats the point? Its not a rich market you can tap. Most people see it as "if the developer isn't making money off of it anymore, its a-okay to pirate". You don't see people with reservations for N64 or SNES piracy because that market has been tapped, sucked dry, and then buried.
In a situation like that, I would think to myself - "Alright. Which is better. Funding a corperation with shitty business practices that rips off users, sells products at hyperinflated rates, and is considered one of the worst places in the world to work for, or download a ROM - which doesn't negatively effect the developers because the company stopped producing the game?"
Even if the game is re-released, its not really a matter of 'work', it was just re-purposing data that already existed - something an intern could do. And lots of companies are getting into the habit of releasing both hardcopy and digital re-releases of retro games.
You can't walk into a market that already has a very dedicated fanbase, apply your shitty business standards, and expect for it to be a success. People who want retro games can find retro games, for cheaper than what you'll offer. People who want to get rid of retro games can get rid of them for more money that what you offer them. And entering into a direct competition with pirates, over an issue that very few have qualms about pirating with is just asking for massive losses.