Why do some people think they are a door?

Let me explain. Every morning I catch a train on my way to work and have to p through the ticket hall to get from the street to the platform. There are 2 doors which are always open when the ticket office is open and I often find my way through the one leading to the platform blocked by someone. I am always polite and say excuse me, and they seem astonished that someone actually wants to p through the doorway to the platform side. There are several different people who do this so I'm wondering whether they belong to some sort of strange door cult. Do they see themselves as mystic guardians of the doorway perhaps? Alternatively does anyone think that they are looking for Narnia and stop dead in their tracks when they don't see what they were expecting, but are confronted by a railway station platform instead?