What's the big deal? This kind of thing happens all the time in my shop. Instead of having elves tailoring clothes while I sleep, they stack and organize my tires...
...come to think of it, I bet that Pscholte's oil stash stacks itself just like this, too. He IS the Elfmeister, after all.
Well, I guess it is unusual to catch the elves in action on video. Nice link!