This is true. I should have used the term “billing management.” The opaqueness you mention I like to think of as a firewall between the developer and the user in terms of billing. I can truly say to the user: “I’m sorry, but I can’t help you with that.” Many times that’s bad, many times that’s good, and not because I don’t want to deal with users but because I like when users have uniform, familiar experiences that they understand. The clearly divided responsibilities (developer provides software, Apple provides billing) helps maintain focus on product.