The accumulation of people in narrow passages

Why are folks always used to stop (and e.g. have a chat, coffee break or football match) at the narrowest possible point? I absolutely hate that.

Example: lecture theatre in the second floor of the building. After the professor's relieving words "that's it for today", I try to make my way out of the mouldy room as fast as possible.

• Obstacle number one: people packing up their stuff in slow motion, trapping me in the row. Solution number one: jump over the bench (thanks god to my crappy glasses, I usually sit in the front row).
• Obstacle number two: the stair case with students moving downwards at even-slower-than-granny speed - a little kick in their asses becomes a big temptation in such moments.

However, as this would be a far too obvious offence, I'd rather have telekinetic powers to simply prod them out of the way (or throw them off buildings, down the staircase, etc.). When they turn around to peer for the culprit (well, if they still can), I would innocently make my way through the crowd while whistling "fuck the system" and maliciously smirking inwardly.