Watch the part of the movie where Lloyd and Harry are lying in bed watching tv. They are crying over the whole, Little House on the Praire/Pacific Bell commercial. Well, too bad U.S. West is the phone company here in the Rocky Mountain region, and not Pacific Bell!
They may not be in the Pac Bell service area, but I live in Dallas and see WGN from Chicago and all of their local commercials. The same with TBS in Atlanta. Could be they are watching a station of that caliber.
Er, I dunno. I live in Washington, and I see Sonic commercials all the time. I'm pretty sure that there isn't a single Sonic in the state of Washington. So maybe...?
Satellite is plausible, too. Or even cable.