I found this super interesting paper about crowd flocking if you're interested in learning more! https://www.cs.auckland.ac.nz/research/gameai/dissertations/Hurk_BSc_09.pdf
This article about an interview with the principle programmer who worked on Planet Coaster (game where you manage a theme park) was really interesting as it focused mainly on creating believable crowds. http://www.gamasutra.com/view/news/288020/Game_Design_Deep_Dive_Creating_believable_crowds_in_Planet_Coaster.php
Do people really move like this? It seems most people ignore the exits in the middle and are willing to wait in long lines to exit from the side.
This type of simulation actually has a lot of applicability in movies as well:
I learned that there is a film making software that uses physical simulation to render autonomous crowds in movies. It was originally developed for lord of the rings, and has been used in many hollywood blockbusters. Some of the results in the video above are really cool. It's amazing how physical simulation can be used to create really complex and realistic looking dynamics.
One interesting way to simulate such traffic scenarios might be to simulate random particle systems that generate similar dynamics in certain limits. e.g. see http://simulations.lpsm.paris/asep/
Fascinatingly, these models exhibit beautiful and complicated mathematical physical and mathematical phenomena. Some of their properties could be used to simulate real systems.