Why do we collectively lie to (and elaborately deceive) children in the name of holiday magic?

Parents are doing it everywhere.  Right now.  Even people without children are participating in the widespread coalition of lies that promotes Santa Claus, the Easter Bunny, the Tooth Fairy, Leprechauns, Elf of the Shelf, and who knows what next thing - to ensure children believe in something magical with consequences.  This is problematic because 1) it's a lie; 2) it is confusing to believe one day in fantastical realism only to have it shattered later; 3) it is passing the buck for having your child fear punishment or lack of rewards from a magical third party with omniscience and great power instead of them learning to respect you as parents and behave well for its own sake; 4) it is childish and potentially fear-based to think our best option is to lie to children, make-up creatures that are monitoring their behavior and rewarding them independently of anything they know to be true in reality; 5) it causes children pain and a sense of betrayal upon learning the truth, not just of their parents but of all adults that have played along in their lives.  It is a difficult journey to trust adults again and trust their own reality - what they understand to be true and real.  

Why create all of this trouble?  Is it, in part, so that we can enjoy 'our turn' of telling the lie and imagining the magic being experienced by our child?  I guarantee all of the magical, wonder, and joy can be experienced during these holidays by openly pretending together.