The "free riders" aren't developers in general, they're the developers not paying for their portion of the upkeep. Like I said, someone has to pay for the dev work that goes into making the platform, building the SDKs and maintaining the whole thing. No one works for free. So Apple can get that paid for either by charging more for hardware, charging for access to the dev kits, or taking a cut of sales for products produced with those dev kits. Apple chose the later.
So now they have a problem, not all software is monetized. You want to have the ability for people to choose to distribute software for free. Open source projects, educational, charity, and also "accessory apps" (think your bank app). But you don't want to charge developers money that they're not making. Imagine the shit storm Apple would stir up if they just started charging free apps a monthly fee to be listed in the app store at all. You also want to have young and new developers without a lot of capital to have access (that's why so many companies used to offer student discounts). But the problem becomes how do you allow that, and also allow in app downloads and purchases without every developer just having a "free" downloader app that then downloads the real application code that you pay for separately?
Let's say you sell a dev tool. And you decide you want to support open source projects, so you offer free licenses to any open source project. Would it satisfy your licensing if some company that had an "open source" curl wrapper that downloaded and executed binary blobs for which there was no source code? I doubt it. You'd rightfully say that an app that does nothing except download and launch closed source binary blobs is not in and of itself an open source project for the purposes of your license. It's the same basic idea for Apple. An app that only serves to download or unlock the "real" app after you pay the developer in a separate external transaction is not a "free" app of the sort Apple intends to allow. So they don't allow external transactions at all except for a narrow set of circumstances, and in those cases they don't allow steering. This maximizes the number of developers who are funding the costs of the platform, reducing the overall cost for all the developers who are paying and subsidizing a limited set of developers who are distributing free applications.
Or to try one other way of thinking about it, everyone hates the "freemium" business model. How much crappier would it be knowing that all the "freemium" games were paying absolutely nothing, but everyone who chooses not to engage in the freemium model still had to pay 15-30% to apple on their revenue?
So now they have a problem, not all software is monetized. You want to have the ability for people to choose to distribute software for free. Open source projects, educational, charity, and also "accessory apps" (think your bank app). But you don't want to charge developers money that they're not making. Imagine the shit storm Apple would stir up if they just started charging free apps a monthly fee to be listed in the app store at all. You also want to have young and new developers without a lot of capital to have access (that's why so many companies used to offer student discounts). But the problem becomes how do you allow that, and also allow in app downloads and purchases without every developer just having a "free" downloader app that then downloads the real application code that you pay for separately?
Let's say you sell a dev tool. And you decide you want to support open source projects, so you offer free licenses to any open source project. Would it satisfy your licensing if some company that had an "open source" curl wrapper that downloaded and executed binary blobs for which there was no source code? I doubt it. You'd rightfully say that an app that does nothing except download and launch closed source binary blobs is not in and of itself an open source project for the purposes of your license. It's the same basic idea for Apple. An app that only serves to download or unlock the "real" app after you pay the developer in a separate external transaction is not a "free" app of the sort Apple intends to allow. So they don't allow external transactions at all except for a narrow set of circumstances, and in those cases they don't allow steering. This maximizes the number of developers who are funding the costs of the platform, reducing the overall cost for all the developers who are paying and subsidizing a limited set of developers who are distributing free applications.
Or to try one other way of thinking about it, everyone hates the "freemium" business model. How much crappier would it be knowing that all the "freemium" games were paying absolutely nothing, but everyone who chooses not to engage in the freemium model still had to pay 15-30% to apple on their revenue?