Also unless that was a Platinum Hits copy of the game you got screwed there as well. The Platinum Hits version of the game has all of the bonus content that was originally on the bonus disk in the Limited Edition, plus it comes with the first of the 2 ME DLC packs (and the only good one) for free to install via the bonus disk.
Yes that is better than Gamestop's used price for ME 1 but every Best Buy I go to and a lot of Target's, Walmart's, KMart's, and Toys R Us's will still have the PH version of Mass Effect 1 instock new for $19.99.
Now GTA 4 for $12 is a good price. Some people got it for $10 new on Black Friday, but you can't expect a local store to match that, and that's still a really good price for that game. I think Saints Row 2 is better, but only myself and Cheapy D seem to have that opinion.
The prices you mentioned on the FF stuff is ripped straight from EBay. There's no way I'd get rid of my disk copy of FF VII, even though my old roommate (whom I gameshare with) got the digital version of VII and I have it on my PS3. There's no way they're going to sell FF VII for that considering the digital version is $10. There's a reason it's still in the top 20 downloads every week on the PSN. Stores that do stock it want $100 for it.
It's important to support local, independent shops when they give good customer service, but beware if you're going to brag about them and we see that you got somewhat swindled, we're going to educate you about it so you can be a more informed consumer.