I remember Toys R Us as being the *most* expensive place to get NES games. I don't think they ever reduced it below the manufacture retail price, even months/years after a release.
The only time I ever saw a discount on anything Nintendo-related at Toys 'R' Us was when the Virtual Boy was discontinued, and the system was like and the games were . I really wish I decided to pick up as much as I could, but I was in college and I couldn't justify spending my entertainment budget on crap.