Living Inside a Storage Room

If life is a simulation, like some have suggested, the player must've forgotten about it.  Maybe it's running in the background and doesn't use enough resources to slow anything down.  Or maybe the player has just turned off the monitor and is letting the whole thing run its course.

It's probably on some old PC running in a closet somewhere at a celestial university.  A student wrote the simulation to be used for some ridiculous thesis, storing it in a closet for a semester while collecting data.  Promptly abandoned when the thesis was rejected, the aging computer has been sitting there for eons, plugged in and collecting dust. 

Now, everyone just assumes the closet belongs to IT.  The electrons making up our whole reality only exist because no one knows that they can just flip off our switch.  Someday, a janitor will shove a vacuum in there and accidentally unplug us.