So I was watching Candid Camera today, and they had a segment where unsuspecting people who held the door open for others ended up standing there, and standing there, and standing there while a flood of Candid Camera employees pretended to be exiting the store... it was funny, because that ALWAYS happens to me! I hold the door open for one person, then all of the sudden, I find myself standing there for up to five minutes because traffic suddenly increases with people going both in and out.