I think that the pre applied ones shouldn't be removed, and are quite thick and difficult to remove. So if the screen protectors in the box have normal thickness my guess is that it is to protect the screen protector from getting scratched. A scratch protector for a scatter protector
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer?