What the Hell is Elf on a Shelf

Am I the only one that doesn’t get the point of this whole “elf on a shelf”  thing?  I’ve only become familiar with it in the past year and even at that I’m not sure I really get it.  So from what I understand, you hide this little bugger and the kids go wild over finding it.  Why would they want to find it!?  It looks like a creepy relic of 1950.  I’m not so sure about this one…