Being Able to Reinstance into House

[ValkyriaCrystalis]

House interiors are instances all their own. When you enter, it opens. When you leave, it closes. That's why it works the way it does.

Seems logical. But how come we can reinstance in an inn room ? (Genuine question really, I can’t see the difference between my home and an in room ; imo, those are same type of instances, no?)

Edit : saw Enkidoh answer as well, furnitures are differents in each player home, not in the inn room I guess.