When Bloomberg reported that Spotify would be upping the cost of its premium subscription from $9.99 to $10.99, and including 15 hours of audiobooks per month in the U.S., the change sounded like a win for songwriters and publishers. Higher subscription prices typically equate to a bump in U.S. mechanical royalties — but not this time.
By adding audiobooks into Spotify’s premium tier, the streaming service now claims it qualifies to pay a discounted “bundle” rate to songwriters for premium streams, given Spotify now has to pay licensing for both books and music from the same price tag — which will only be a dollar higher than when music was the only premium offering. Additionally, Spotify will reclassify its duo and family subscription plans as bundles as well.
Here's a link with more info
And specifically to your point
That alone should be enough to get people considering other options. I'm sure there's more beyond the big three too.