If you are looking at whether this belief is the trick of the ancient people. They do, in order to teach us manners and treat themselves to a home visit, no people to lie across it will show clutter and bad manners.
If you believe this is a trick of the ancients. They do to teach them manners and behave correctly when people come here, go home, not horizontal passage because it looks disorganized and rude.
If you see this belief is a trick of the ancients. They have to teach us courtesy and behave correctly when people visit the house not to sleep in the way walk because to see the clutter and rude.