Because G2k doesn't give out enough store credit, etc for games. Gamestop gives out more.
For example, I got credit for a game I had, I think I got $10 or so... and well like a week went by and I still had the receipt and money they gave me and I wanted the game back, just even trade. They said NO,because it was theirs now and they wanted more than what they gave me and that I wasn't the person who traded it in. So I was like whatever, no big deal, so I go to Gamestop and they have a copy of it in stock... for $10 less than G2k. So, I came out on top of the deal. Also at Gamestop you trade in any three games and automatically get %10 off, and I mean any three games you want.
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