Yeah, to be honest, I don't think Spotify is going to continue to grow at the rate that it has the past 2-3 years. Plus, their contracts with the major labels are running out very soon and the labels want them to make it less free, yet, Spotify on the other hand wants to pay the labels even less and do nothing about how free it is.
Yeah, they want to down royalties payouts from 55% to 50% for master right holders because of IPO but don't forget that Spotify paid 84% (not 70%) of its revenue to labels/publishers in 2015.