Creature-house entrance relationship

I'm running the classical old StarWars marathone, and I can't help to interrupt a sec for blogging about a detail I noticed only now and always eluded me earlier:

C-HE relationship: the shorter the creature, the rounder the house door.

That  holds for Yoda, for the Ewoks and even for the Hobbits of the LotR trilogy!!! I don't remember about Willow, though.

Have you observed other manifestations of that law or counterexamples?