I don't think most people listen to 300 tracks of any artist per month consecutively. Say you are doing 30 tracks per month on average by an artist, that's $5.66, less than buying three 10 track albums.
I have hundreds of albums on CD (I'd guess ~500 or 600). There are many that I probably only listened to five times.
My main gripe is that because of this stupid model, it pushes a lot of the artists I would listen to away from spotify because it doesn't connect them directly with the revenue stream they should be getting from their true fans. Artists have a hard time surviving without that.
But there's a separate listener: the explorer. The value of any given track is exceedingly low, but these are the people you depend on for the discovery function. Personally, I prefer that role, but the cost before Spotify was exorbitant unless you were an industry insider.
If you think on principles, Spotify should in the long term aim for maximum customer satisfaction. This means optimizing the satisfaction per customer instead of per music play, seems to be currently done. By concentrating money on bands each user listens to each of those bands (getting more money) should theoretically improve in quality (and give Spotify more attention), increasing overall user satisfaction. It's a simple reasoning.
I listen to Spotify and Pandora almost exclusively. Mainly Spotify. I probably listened to 300 tracks of Emancipator a month on Spotify. At 0.00786 per play, that works out to 2.85. For the last 2 years: 2.85 * 24. That's $56.59. I seriously doubt I would have spent that much on iTunes. In fact, from their site, I can only spend $46 on their music.
http://emancipator.shop.redstarmerch.com/Dept.aspx?cp=69283_...
In the long run, it seems to me that Emancipator is winning on Spotify, even if I overestimated by a factor of 3 and only listen to 100 tracks a month. Presumably, I will be listening to Emancipator for a long time.