How to rescue smoothie stains on the wall?
You may have to get a ladder, assuming you don't have one tall enough.  You could decorate the rest of the wall with more smoothie but painting would probably be the best bet. :)  If you do paint, test on some lower stains first and give them at least a day to see if the stains bleed through the paint.  It would be safer to just use some Kilz primer to seal the stain spots before repainting the wall.