The seats are assigned. People have been standing in line for 15 minutes now. Why on earth would anyone want to stand there, when they could just sit and wait until the line clears?
I understand wanting to get off a plane ASAP, but boarding? You just end up sitting on the plane, waiting for everyone else to get on.
The sooner I get to my seat the sooner I'm out of the god damned airport and can begin whatever escapism I've chosen for the flight. The thing I truly hate is the airport and being in it.