That's because the pricepoint is ludicrous. If I buy two CDs a month, that's more money that both creator and music business will see than a month of Spotify. (Now, I happen to buy the CDs and use Spotify as a discovery service, but most people think their moral obligation is satisfied when their legal obligation is.)
Further, free/cheap alternatives reduce demand for premium services. Why would content creators cannibalize their own revenue streams?
If you feel a moral obligation should come into play then you shouldn't be buying CDs or Spotify. They both serve to prop up the copyright industry with their perverted ambitions to retard human culture and development in exchange for short term profit.
We have a fundamental difference of ethical concerns here.
I'll be on board with your view once we reach post-scarcity, but right now humans still need to eat, and high quality production still requires money to produce.
Every hour that a quality musician can afford not to work is an hour they can be working on refining their craft. It has already been shown that touring pays less than minimum wage (yes, including those fucking t-shirts) for all but the top acts, so the purchase of music is one of the few ways to stay afloat.
The truth is, if we support the musicians that make the music which we want to hear more, then we will get more of that music.
I'm an ardent supporter of Lessig et. al, but the proposed alternative revenue models aren't working.
Further, free/cheap alternatives reduce demand for premium services. Why would content creators cannibalize their own revenue streams?