Re: Says who?
Like radio before them, streaming services like Spotify and Pandora aren't there to support musicians directly. They are in the same domain of "free content" that the industry has always had since the dawn of broadcasting. The true value of any broadcast or streaming medium is the fact that it is getting you exposure.
No one will buy your stuff if they don't know about it.
People need to know about your stuff. Clear channel dominated radio is a dying dinosaur that may or may not give you any airtime. If you ever hope to sell another album again, you need an alternate promotional medium.
Musicians only harm themselves with this nonsense.