Probably would be deemed to violate the Guidline that "You must not directly or indirectly target iOS users to use a purchasing method other than in-app purchase, and your general communications about other purchasing methods must not discourage use of in-app purchase."

This is why I'll never 'purposefully' own an apple product. I made a client buy me an iphone to test out their ios builds from (I'm the api/backend dev), I'll probably someday do react native stuff/cross platform and might cringefully get a cheap old mac just to build the ios app, but I'll do it begrudging the whole way to the app store..lol

Your post makes the case for itself, 30% of $13.32 is not $3.33. As Spotify raised their price to counter the apple fee, the also had to give 30% of that raise.

To get $9.99 (for the first year at the 30% rate) it'd be

Spotify fee: $9.99 Apple fee: $4.28 Total: $14.27

When they were charging $12.99 on iOS Spotify was only taking home $9.09 and Apple getting $3.87.

Really goes to show the insanity. Apple probably made more from a Spotify user than an Apple music user. (Of course, they're happy to have an Apple music user for the increased lock in.)

(But as others point out, Spotify showing this almost certainly wouldn't be permitted by Apple).