That's not quite what I meant. Basically a dev would sell a Reddit client for a fixed amount and when the user would fire it up to view Reddit, then that would

That's not quite what I meant. Basically a dev would sell a Reddit client for a fixed amount and when the user would fire it up to view Reddit, then that would trigger a native Reddit's API subscription, paid by the user directly to Reddit. This can be streamlined to be nearly zero-friction IF it's supported on the Reddit end.