[Grubhead]

Radio stations have to play performance rights fees for every record they play. So yes some records will be cheaper to play than others. Hence the playlist of the same records over and over again.
If you fill up the shows with phone calls and news and chats, that saves on record fees. It was an old technique from the days when Radio Stations had "needle time". Where they not only paid a fee for the records played, but also had a maximum time limit of the total recorded music played. Live music didn't count, since the musicians got paid anyway. Of course the old Pirate Stations didn't pay anything and didn't bother much with needle time. However later the did start paying to put the critics to rest.

So it's very expensive to play a record on the radio. What gets me is that the record companies often get two fees for it. First from the Radio Station, then if it is played in a shop or other place where the public could listen to the radio, another fee from the shop. A local hairdresser, who didn't have music playing, told me she was constantly being harassed by the officials set up to police the scheme. Checking if a radio had been sneaked in or was on the premises.