I not know how / why it happens… Only that affected users helps to start the application with admin rights.
I assume there is as some reason a file / folder / … changed in a way that users need admin-rights. May be these users started the application one time with admin-rights. Some users tried to re-install the game to fix that, but in this case it is also important to follow the official FAQ and manually remove folders / files which are not auto-removed from uninstaller procedure.
( FAQ: uninstall MS-Store , uninstall Steam )