I am undable to delete purchased tunes from my iPhone (4s, ios7.0.2) I can delete all other tunes through syncing on iTunes. However, purchased tunes remain on my iPhone. To the right of the title of the tune there is an image of a cloud with a arrow pointing downward. This indicates that the tune is to be downloaded. This is strange, as these tunes are already in iTunes. I tried touching the cloud to download the tunes onto my iPhone. Once all were downloaded, I went to settings, general, usage and to the music app. The I went to edit and delete. This did no good. The tunes are still there. I have tried this several times. On my last attempt, I download the tunes again (on my iPhone), the synced with iTunes. The tunes on my iPhone were temporarly gone, but soon came back. I do not want any of these tunes on my iPhone at this time. I don't know how to get rid of them.
If you read carefully and go to the actual page under settings>Music> show all music
You can see it's written to show music from iCloud and the music that has been downloaded.
So if you disable it, it won't disable all your songs, only those in your iCloud's.