I think the point of robbing a house while the occupaints are asleep is to avoid the occupants and leave before they wake up.
Which, I would think, would mean avoiding getting to close to the sleeping occupaints. So no, I don't think burgelers would be checking the nightstands.
Mal: "If anyone gets nosy, just...you know... shoot 'em. "
Zoe: "Shoot 'em?"