Although the RKO prop department did a good job with the layout and style of each state's license plates that Corby sees parked by the general store, all were flat-painted and not embossed as they should have been. And there should be no period after "ILL" on the Illinois plate.
If a person honked her car horn as often as Simmons did, she'd be arrested for disturbing the peace. In addition, she abused the medical-alert horn for frivolous reasons, another misdemeanour.