An excellent idea... Yes, Virginia, there is a Santa Claus; he's just not in our world.

Here's a little exercise for MWI fans: estimate how many worlds there have to be before we can be sure Santa exists in one of them (his sleigh flying around because of random molecular collisions, getting into and out of houses by quantum tunnelling...)?

Stuff like this reveals just how strange MWI is, and the attractions of single-world interpretations.