What is it that Gamestop are doing that is harming, and who or what is being harmed?
DJ
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they are making a remarkable profit from second hand trades, with each trade they are speeding up the process of the second hand market as it provides a reliable outlet for bad games to be traded.
The direct victim is the developers, since the ease of getting second hand games will hurt first hand sales, which means they will have to recover some profit by the means of unlockable content thru one time redeem codes, it's more and more often that you won't get the full game unless you enter a code that comes with the game, and that practice will in turn harm people who don't have regular internet access from their console.
And this business model also means game sales after launch is pretty much none, since everyone can get it second handed. Hence publishers do hype up games even more to ensure first week sales, since that is where most of the money will come from, it means we will see more time devoted on making glorified trailers rather than actual good games.
In a long term, everybody loses, while gamestop is making repeatable income, increasing its influence in how games are published.
I have no objection of buying second hand game from other people or passing it to your friends, however feeding a giant retail chain for minor convinence, and taking this trade for granted isn't good for the game industry.
As for rental, unlike videos which are protected by law that shops can't rent out retail copies, but instead have to buy a more expensive rental copy which grants them the right to be lend out (which is a logical protection of the video maker's benefit). Right now no law protects the publisher of video games, so unless it is put under legislation one day, you are practically renting games that the shop had only paid once, people can abuse the renting system and the publisher will get absolutely nothing out of it.