I love the concept that the Riffs are from Gramercy...makes me wonder what sort of terrifying gimmick gangs ran Brooklyn Heights and Murray Hill thirty years ago.
By the way, if you're thinking of getting the "Director's Cut" version of the movie that was released a year or two back on DVD -- DON'T. It's got an awful new prologue and removes key dialogue and classic shots from the original release so as to insert clunky Video Toastered 'comic book page' transitions between scenes.
I'm gonna have to grab the old version off Ebay soon.