There's little pretense that the music drastically changes the world at large, either. Sure, people would buy another Doors album or another Beatles song, but no one really needs them. The book doesn't pretend otherwise. So the music is just a hook, an entryway. A way to disarm narrative expectations, to distract us from the story-ness of Ray's stories, and to defer our questioning the motives of that storytelling.
Stories are nice, but their connection to Real Life is too obvious.
If your hero produces stories, the readers are going to be looking hard for hidden motivations. All it needs is a hook. Now, the hook of a pop song isn't disguised. It isn't baited. On the contrary, the bait of the song is the hook.