US Radio Stations pay ASCAP licensing fees, which go to the composers, writers & publishers. When most musicians put out a album, they must create a 'publishing' entity so they can get paid royalties. When Radio stations play the records, they must pay ASCAP a licensing fee.
You could argue producers aren't paid directly sure, but most people think of the performers as the writers/composers. So I believe radio stations DO pay artists... via ASCAP licensing fees paid to them as royalties.