The Great Bank Robbery - S4-E6
Revealing mistake: The bandits lock Bo and Luke inside closed coffins and then leave. Bo and Luke begin "rocking" the coffins back and forth to tip them over so they can escape. However in the following shots, as Luke is rocking inside his closed coffin, the camera slips or shifts too much, and you can see the barns' interior at the sides of the screen, alongside some equipment.
Answer: Various reasons, but mainly to drive the Dukes out of Hazzard County because the family have been foiling his schemes since his and Uncle Jesse's bootlegging days.
Captain Defenestrator