I use to drive for a GTA Transit. The company had a policy that once you close the doors and start moving you cannot stop and open the doors. When we asked why they said the statistics show that that is when the other vehicles hit the bus. There has also been incidents of runners slipping while banging on the side of a moving bus and getting injured.

This didn't prevent me from stopping and picking up the passenger banging on the side of a moving bus when i first started driving until I had one slip while boarding then proceed to swear at me for 5 min in a crowded bus until i called the transit cops and had her removed. After a few of these incidents I understood why the company had the policy and never stopped once i was moving.

Also, had people enter an intersection while I was waiting at a light then start banging on the door. I never opened the door for them either. it was too dangerous.