Plot hole: When Bill and Clark are discussing the bonus delivery situation, it is December 21st, and Bill says his son received a delivery at his home via company courier. The bonus checks were to arrive to the employees before Christmas Eve, which would have given them plenty of time to contact each other that none of them got the bonus checks but did get enrollment in the Jelly of the Month Club.
Plot hole: When cousin Eddie kidnaps Mr. Shirley, Shirley's wife immediately calls the police. She describes Eddie as 'brutish and huge' or something similar, and wearing a 'blue leisure suit'. She also mentions that she got the license plate number of the vehicle. But how did the SWAT Team know to go to the Griswold's house to find Mr. Shirley? Eddie's RV is not registered in the Griswold's name so the plate numbers would not be much help in finding the culprit.
