The reason I suggested checking the cars is actually Binky's description of the ghost, and that it's animation's simply swinging back & forth.
With such a simple image who's only animation is swinging back and forth, it could theoretically be getting used as an in-car air freshener (the kind you hang from the rear-view mirror) Another possible use could be as a "wind chime" of sorts, with it hanging outside one of the buildings somewhere.