And here is another parallel. Dark Knight implies that a large supernatural bat haunts the Cave and possesses Wayne. In Dan Dreiberg's basement workshop, the Nite Owl costume, standing upright in an open closet, seems to watch Dreiberg, who says that he feels like something is watching his every move.
It as if the costumed adventurer identity, manifested in the costume, watches and waits for Dan to resume adventuring. Of course, this identity is not in the costume but is inside Dreiberg himself, like the Bat possessing Wayne. Dan's feeling of being watched reflects the gradual reawakening of his adventurer identity which becomes fully awake when he re-dons the costume.
The Owl waits in the basement as the Bat waits in the Cave.