I used to work at gamestop about 8 years ago, and I can attest that the store has gone to shit. I got hired for xmas but then they kept me on and I eventually became a third key (kinda like a manager). Anyway, I worked one night a week and all day Sundays (and got to hand pick my own crew, which was awesome btw). There were 3 of us (sometimes 4 on holiday weekends) and I ran that store to perfection. We had the best Sunday numbers because we were all personable, and people even told us that they only came in on Sundays because we worked there. I ran a tight ship too. We had one register strictly for cash only, and one for just CC. Kept the store flowing. I would let my guys work the registers while I helped people. My manager was a pretty good guy too. He allowed me to vary trade in prices to a point that helped customers (example, I would add a few bucks here or there to a trade in for someone who wanted to trade in a few games for one new title).
I think the biggest thing that actually hurt Gamestop was when the bought out EB Games. We had an EB games in our mall and people always preferred us over them. The only time they went to EB was to buy PC games since we didn't sell them. But when they got bought out, everything started to change, for the worse.
In the 2 years I worked as a manager, we had 1 customer complaint, and it wasn't even our fault. Some punk kid and his dumbass father come in and demand a refund on GTA cause the kid was 13 and he bought it without his dad's permission. I told him we can't return open games but I would call my manager to see what we could do. So I take a look a the receipt, and #1 he bought the game in PA, not our store and #2 he had it for 3 months. I looked at him, and I flat out told him "Call the store on the receipt, we can't do anything for you". He starts cursing at me and wants my DM phone number, I just laughed at him, said "here's his number, good luck" and he stormed out. Few days later my manager call me in and said "that guy called the DM, and the DM told him too bad... it was hysterical..."
We had another lady complain that she bought a PC game from us and we never put the game in the box. To bad we don't sell PC games at our store. We argued on the phone for like 10 minutes before I just hung up on her.