@LukeAlmighty @gear games do not need installers. They can help reduce download file size, help with user organization, and that's it. Pirates like fit girl have their own custom installers to shrink the data as much as possible and only unpack what's necessary.

I don't even know how they are going to track this period. It'll probably be on the game developers themselves to ensure they pay Unity for x amount of installs unless they want to have their game removed or be sued, if Unity knows they haven't paid up. Realistically, the only way for them to know for sure would be by putting spyware into the Unity runtime or something, but even then you should be running pirated games offline so they wouldn't be able to tell. They can guess how many people have installed the game perhaps by community interaction or review counts, but that's it.

Unless I'm horribly misunderstanding something. Unity doesn't, by default, have access to the number of installs a game has. The developer and the platform know that, and can choose to disclose it if they wish.