I did too. GME may rule the used market and the big boys may not have been successful in dethroning them, but AMZN seems to crush them on price all the time, not to mention sites like GOGAMER and Newegg. Almost always free shipping and of course no sales tax.
These online outfits like Amazon have the no sales tax advantage over physical store models. That is something to note alright. Free shipping and no sales tax? Fantasy world. Amazon has physical warehouses that they ship from. This has tax implications for them that you are not accounting for. The only way Amazon can do this is to sell at a loss, to try to chase competition away. That sort of approach is not sustainable for them.
Not sure if you are disputing the free shipping in your last comment, but obviously you can check that for yourself and see it is true. I can't remember the last time I paid a shipping charge for a video game, not even on the full Rock Band 2 game in Dec which was $88.
Single games don't cost much to ship at all and the free shipping is no more than UPS Ground at best and some times USPS. I imagine their (AMZN) volume is so huge it's probably even cheaper than most would guess.
They can keep this up because another advantage they have is being a department store than make make up for small profits on these games perhaps on other, higher margin items.
What do you know? GME is finally getting in the game! Banner on their site now offers free shipping on orders over $25 just like AMZN. Details say can be cancelled anytime without notice, but I think everyone says that.