In America, you can't stop people from using your music. You just have to pay them for it. And if you price the music high enough then, you effectively stop it.
Music in America is licensed for different venues, and at different rates. So while your TV shows can have music for broadcast license or Netflix, it won't be available for DVD, because of the cost.
Part of the reason is it's so easy to rip a DVD or BluRay, yes even with copy protection its a simple matter to get around that. Then you now have the song. So in a sense it's ownership of a song. Yes a 30 second Aretha Franklin song off "Murphy Brown" is a ridiculous thing to worry about someone owning, but they want to prevent precedent.
So by pricing licensing rights so high for DVD/BluRay releases they know if they have to they can recoup the loss (or perceived loss) should it come to that.
Now add to this things like, notice I said, "In America" in other places of the world an artist CAN prevent his/her songs from being used. So the DVD/BluRay distributers want to avoid a situation where a BluRay could be issued in America, but not Europe.
Well fine, but how hard is it to switch regions or get a region free player and just buy overseas? It's easy.
And finally remember a lot of artists/songwriters don't own or no longer own their collections. So a company may say, "If you want to use Aretha Franklin in 'Murphy Brown', you have to use Joe Schome (also part of their collection) in series XXX," which the company has no desire to release.
So it's a bit more complex when you start looking at the large picture.