Not to be too harsh on Gamestop, but that's like applying for a McDonalds position
I'm going to tell the story of a friend of mine which shall remain anonymous.
That person worked in the games division of an electronics shop much akin to Gamestop for a few years.
She is now in the game industry. And yes, the position she had was instrumental in securing that job.
Whatever the job you do, you can 'do the job' or 'DO the job'. Sure, you could just tell people in what row to find the game they're after, or when its released, or you can work out a deal with your boss (in case its not already up) where he allows you to play all of the games for free in your spare time, so that you always have something to say about THAT game. You may not realize this, but the industry needs people that are able to tell apart a 'good/bad game' from a series of 'good/bad decisions'. From my perspective, there are a lot of people upstairs that can't quite see the chain of decisions that lead to a bad game, and this means they are going to repeat the same mistakes again.
Personally, I think landing a job at Gamestop may be beneficial to a game dev career if you get in there with the right mindset. It can help you refine your 'critique' sense and give you a broader understanding of game quality which is, once again, instrumental in getting polishes games released.