Honestly gamestop isn't all that bad. Sure their values for trade ins suck...so don't trade in to them. However compared to most places around me, their prices are pretty similar to other used places, and they tend to have better stock, not to mention the guys that work there are nice as hell, know what they are doing, and if you actually talk to them, they can, you know, get you the copy that hasn't been opened to put on the shelf. Sometimes they don't have them, and then its up to you, but gamestop never forces you to trade in or buy what you might see as used because the package is open. I mean sure I think the trade in prices could be better, and certain other things..but they are a large business.
And ive always pre ordered through the store, and if I decide I don't want the pre order anymore, they are MORE than happy to let me transfer it to something else I want (or give it back, but ive always just put it on something else I want more.) Hell the ones in my area have been cool enough to drive to another store 20 minutes away to pick up a 360 arcade unit when I needed to replace my e73 error one I bought years ago, and have allowed me to return a game I purchased new, but was one of the shelf copies so it was opened, since I hadn't played it. I think it just depends on the store, and the area, but the ones near me are pretty cool guys, so I dont get all the hate to be honest.