I remember about 10 or so years ago that Game Force that was on Broadway and Belleview had a booger-encrusted Contra for NES and they wanted $50 for it.
Reminds me of this one store here in Abilene, TX called "Manuel's." He writes the prices for the games ON the games themselves! No stickers, he just sharpies them on the disk case or worse... the cart itself! And said prices are the typical "looked 'em up on eBay" variety.
That said, I keep going back there because every so often, he'll have something at a great price that I just can't pass up. And that's how I got Crue Ball for my Sega Genesis, CIB, for $5. (And he actually had a sticker on this one!)