I worked / managed an EB games for 6 years before moving on to my current job. I understand why they gut copies of their games, it allows people to actually read the back of the case and flip through the manual without asking to have a case unlocked. When I would sell a gutted copy of the game I would always ask if the customers would want it re-sealed. Every store has a shrink-wrap machine in the back room, and while re-sealing a game may take time and cause longer lines my customers really appreciated it (especially during the christmas season).
Now, as a customer, I will always try to buy used games from gamestop. But now I am beginning to find new games for really cheap at Walmart, Target, and Best Buy. Also the sales associates in my local store are ALWAYS behind the counter and very informal / casually dressed. Regardless, if you are going to fault anything it should be the work ethic of the employees. I agree with the idea of opening one game so that customers can actually touch the box without having to ask for a case to be unlocked.