Don't you think that as long as it's good users won't care? Netflix would likely have succeeded without originals but would have been nowhere near as pervasive. People were tired of the network crap and wanted content accessible everywhere. They delivered on those.

Good content is good content. For music - it's even better if it's not yet well known because for some reason people think more highly of themselves for being an early fan. Early discovery favors audio moreso than video. So pushing originals (newly signed artists) is a great strategy for Spotify. So long as it's good music.