The Town's Dressed Up For Trial

The whole family seems to be influenced by the look of the Southern belle!
We learn a lot about the culture of the town when chapter 16 unfolds into a parade of town folk on their way to the trial. Ladies are dressed in their hats and gloves, and as the wagonloads pass by the neighborhood, Jem and Dill explain who they all are. It seems like most of the town is there, although Miss Maudie explains to the kids that she thinks that watching the trial is morbid, and it reminds her of a Roman carnival. Though they think Atticus might not approve, and certainly not Aunt Alexandra, the kids sneak in anyway.
Speaking of sneaking in, how about the events of the night before? What would have happened if Jem, Dill, and Scout hadn't slipped out of the house and gone to the jail? How on earth did Scout stop the mob? Did she even know what she was doing? Of course, Aunt Alexandra is appalled by the whole event, but what is her problem with the way Atticus talks in front of Cal and the kids?