how do you suppose they could get a monopoly on that? every time gamestop is mentioned anywhere, there's at least one person complaining about how low they pay for used games. it can't "forget the entire gaming community over" if you're not handicapped. nobody is forcing you to sell to gamestop, and gamestop isn't getting more than other buyers
but you're right, I haven't taken economics
do you know what a monopoly is? If not, I suggest learning that before starting an argument based around it.
If GameStop owns both the new and used game markets, they then get to choose the prices on those markets, meaning neither new OR used is going to be in competition with each other, so you see game prices increase, want a really good example of this?
A new PS2 game (in its era) was $20.
A new Xbox One game is projected to be $80
that's what monopolies do, they increase the price of the base item they're selling, sure a lot of that increase is due to game developers, but I'd give a good $10 of that increase to the developers having to figure that they're going to lose money because of the used game market being as skewed as it is.
Needless to say, if one store focused on just new games, and another on just used games, they would keep each others prices in check, if the used store is a ton cheaper than the new store, the new store then lowers their prices. But I'm not here to teach you economics, go read up on supply and demand if you want.
Monopolies aren't good, and that's exactly what game retailers are doing right now.