AM radio has been the province of sport and talking heads for a fair amount now, while most of the music broadcast moved to FM almost as soon as they could. Out in the Dragon Conspiracy Territory, a lot of our "traffic advisory" signals are broadcast on AM, which would be a reason to keep them around, although it would probably not be all that difficult to reset them to an FM transmitter and repaint the signs with the new frequency demands. And with the increased number of electronic signage boars advising about traffic conditions, accidents, and the various states of passes, it seems like there's a fair amount of redundancy being built into the system.

So I wouldn't be surprised if at least some of this "no! We must have AM radio" push is trying to make the constituencies that have been Dittoheads since Rush started bloviating stay happy that they can get their fix of conspiracies and right-wing talking points as they drive.