How they easily could have escaped...
So One guy in a giant as coat vs 3 adults with no weight holding them down...all 3 ( Or just the guys if the lady is wearing dress shoes) should of just ran out and gunned it...The killer is only one person. He would only be able to chase after one. But also he is wearing a very heavy winter coat which would of slowed him down....Yes I know there is a risk in doing this, but what other option was there? They had so many chances when he was in the back to slowly walk out and then book it. Once they get to the street he most likely would not of kept following.
I know I am taking this movie too seriously but my god.