I actually called one shop a couple years back to get a trade in value, and they said the same thing. It wasn't Gamestop, it might have been EB.
This concept isn't necessarily uncommon though, and I can see some reason for it. If someone calls up and says I have Game A for trade, and he says Okay, I'll give you 15 bucks for that, and then the guy goes in and the game is in crappy condition, I could see a conflict occuring there.
And yes, a lot of it is where they want you to make the 'impulse' sale, which is again, not limited to GameStop or video game stores [check out all the candy/magazine counters right by the register in virtually any store.]
Also, the condition of the game/manual/case I'm sure has an effect on the trade value, which of course they'd need to see the game to judge.
While I don't trade games in often, I'd rather try to sell/trade over the net to other gamers, many people are very 'casual' gamers, and don't want to hassle. They go to EB/GS, offer a game, and get ten bucks off their next game. Whereas at a garage sale or pawn shop, which are probably the most common/recognized other non-internet based game sale forums, they might get three bucks cash. And many people aren't 'collectors', like we are--they buy a game, play it, finish it/get bored, want something new. You have to admit, the majority of people who post on single-theme message boards like this one are not the 'average consumer.' Nothing wrong with that, or with not being a collector. My parents just got into DVD, and the only DVD's they own are the ones we gave them--they get theirs from Blockbuster and Netflix, and can't imagine why I want to actually own 100+ dvd titles. I know people who trade in their car every 2 years, that's the same kind of thing, and they're taking a beating on the depreciation those first couple years.
So while this is an inconvenience, I don't see it as some evil thing only GS does, and of course, any store wants your business, especially if they are giving you service, so they aim their policies in that direction.
I trade/sell some of my games, depending on
A. collectibility
B. replayability [rather, will _I_ ever replay it?]
C. fun
D. how much I'd get for it. If I bought a game for 80 bucks, and would get 2 for it, I'll just keep it or give it to my brother or a friend or someone. Or donate it, and take a tax writeoff of 40 bucks or so.
And I don't think a sticky about trade prices in general would do all that well either--a lot of it would be store dependent, based on their stock levels, their buying market, etc. It might be good as a general benchmark, [as in, Roughly how much might I expect if I traded in XX?, to tell me if it's even worth my time], but don't expect to get exactly what the thread says.
