Thanks for the clarification PixelRebirth. The fewer objects i use in a game the more manageble it is. The game i've created with GameMaker used a lot of unnecessary objects and after a while it become quite difficult to manage. In the example you've provided using the offset command
you don't use any more objects, resulting in a 'cleaner' and easier to understand example.
Imagine a game with twenty levels or so, each level having it's own 'false' objects, things will start getting unnecessary complicated!