Oh... here's a good one from the History Channel!
In a show about barbecue, they stated outright that the reason barbecue developed in the South was... hold on to your chair now!...
slavery! 
The argument, you see, was that because barbecue means slowly cooking meat over a low fire, it was a very labor-intensive way to prepare meat so only households with slaves could afford to cook it.
So, here's the quiz: Who can tell us all of the idiotic errors in the claim that barbecue developed in the South because it is a labor-intensive cooking method that only people with slaves could afford?
In the same show, there was also a blunder about Clarence Birdseye, but it's just plain dumb instead of going out of their way for idiocy like the one above. Birdseye (at least once) demonstrated frozen meat to a guest in his home by tossing it at the floor and it bounced. The ditz they are interviewing said it bounced because meat was not frozen as solid in those days as it is now.