d.j.'s (the D DOES stand for DISC!!)often volunteer their time to program their radio shows....and are not always able to afford to burn songs and tunes on their own budget...so some that are only offered by download or online from dropbox or other source may not get the airplay they deserve due to financial constraints. I know that musicians are sometimes also not able to foot the bill for demo discs, but if all things work as they should they hopefully will have sales of their material when people hear them. As a d.j. I feel as if I am working for the benefit of the artists, and providing a channel for their heard-earned work to reach the ears of the people!!! (and I always try to announce the source of the music and include contact info so that people can purchase the music and connect with the artists.