Yeah, I get what you're saying. But you'd think that if they played them in Baltimore back then, they'd also play them in LA and every other major city...unless they were a local band from Baltimore who only got airplay there.
I think regional airplay is very difficult to predict. I know of several bands that were played in Dallas and the central Texas area (San Antonio and Austin) that didn't get much exposure elsewhere. Zebra had some play, but not much.
Bands like Axe, Moxy, Garfield, Legs Diamond and many others were played here a lot, but I'm not sure how wide spread their influence was elsewhere.