Apple is to Spotify as is the construction company which made the building Walmart is using to Walmart.
I have not heard of construction companies claiming entitlement to a cut of Walmart's turnover.
Every grocer in the USA does this. Want shelf space? Pay me.
Digital assets don’t preclude this transaction.
Behold.
Whether or not one thinks they deserve a 30% cut, Apple definitely works to make sure the App Store can at least deliver the application to the hardware and their interfaces ultimately bring Spotify's interface to the user. That fairly reasonably fits in with "the sale of goods and services to consumers". In-app purchases are more arguable (keep in mind it necessarily uses Apple Pay) but this thinking that the App Store is not comparable to retail seems to be a little narrow-minded.