OK. I’ve been thinking about this wayyyy to much and I have a theory.

Santa uses Quantum Tunneling.
For each time zone, as long as he is unobserved, he can use quantum tunneling to probably visit every house simultaneously. In reality, he only needs to visit one house per time-zone; he just needs to do it all at once.

OK – Now comes the cool part. I hear you say “But wait – when the first child comes down and finds a present from Santa, it collapses all the other probable deliveries for the time zone and on-one else gets one, so it pays to get up early.” but as the present deliveries are not mutually exclusive (Schodingers cat once revealed cannot be both alive and dead, but 2 kids can both have presents. Just look around on Christmas morning) and the discovery of any single present is within the established effect-event cone of all the other present deliveries in the same time zone, time’s arrow says discovering any present this morning cannot effect the delivery of any other present last night, so everyone gets a present.

This only works, of course, if Santa is unobserved as he delivers, so SEND YOUR FLIPPING KIDS TO BED – I WANT MY PRESENT!!!