During the scene where everyone is going to the processing plant in the limo, they drive by the same group of mail boxes numerous times.
When Hanky and Gordy escape from the school bus to climb aboard the feed truck, they do so through the side emergency exit. Not only does no alarm sound when this happens, it is closed in the next shot once they are aboard the truck.
When Jinnie is shown been interviewed on TV, her last name is listed as MacAllister. In the closing credits of the movie, her and her father Luke's last name is listed as MaCallister.
Shortly after Gordy's family is taken away, he was told to go north from Meadow Brook farm. On the map after he accidentally got into the truck, he's heading southwest instead of north.
Interstate 64 heads east from St. Louis all the way to Chesapeake, VA. Krugman states that he and Dietz were about to cross the state line. On the bus, it wrote Kansas City, Kansas. From St. Louis to Kansas City, they'll have to take Interstate 70 West.