My thinking: you pay 21 dollars to see a movie as a couple, and that is hit and miss on a best day.
With Spotify and iTunes, you can easily preview any album out there before commiting to a purchase. It makes it fail safe.
I really like to keep my collections to a few hundred albums and CDs. With Spotify, I make weekly lists, which I listen to on my PC while I work. I really enjoy CDs in the car over more compressed formats.