From how I've had it explained to me, the catch is instances like player house interiors (same goes for FC rooms and apartments) gets unloaded from memory the moment no one occupies it, and you spawning outside the house is SE's countermeasure for the location you logged out from no longer "existing" in memory.

Inn rooms are actually just one prepetually loaded instance, but everyone else except you are set to appear invisible, so it's much less of a risk to retain that position for whenever you spawn back in.


Nevertheless, I'd be WAY behind the ability to log out sleep in our own homes, instead of just inn rooms