Earlier quoted context omitted.
You would buy the CD, or pay for the download. Doing that is way less justifiable when it's available on Spotify.
Do you seriously think people would buy the CDs of all the music they listen to in Spotify if it went offline? And go from spending $10/month to hundreds? That kind of assumptions is what leads the RIAA to calculate losses bigger than the entire world's GDP.
No, but people might do it for the handful of artists they really like or believe in.