Santa is a very far drift from a Bronze Age Indo European god responsible for initiating young men into warrior societies in the dead of winter.  He's apparently been culling from the naughty and the nice in some sense or another since the ancestors of the Hebrews were still polytheists with an uppity storm god eager to get more air time.

*And* true Christians shouldn't obsess about Jesus getting one day of the year, since every day should be lived in emulation of his example as best one can.  Obviously Grisham is full of fail by that metric.