I was a DJ on a volunteer manned radio station where we were our own programmers. We played what ever we liked and it was fun. We had the advantage of not having to worry about paying for anything. No paycheques to cut. No bills to pay. It worked well.
Unfortunately, there are very few radio stations like the one I was at. NPR radio stations rely on grants and donations to pay the bills. Commercial radio stations have to sell advertising in order to stay on the air. Their advertising rates are determined by how many listeners they have. The more listeners, the higher the rates. And you attract listeners by your programming, ie, playlists and to a certain extent, the on-air personalities.
Even the XM-Sirius radio stations have play lists. It keeps their costs down in that they record a program and replay it several times.
I'm lucky where I live because the radio market is so over saturated that if I don't like what one radio station is playing, I can quickly find something I like.