You instinctively move your hand towards the toilet paper roll, ready to finish your business. Your heart sinks as you grasp a bare cardboard roll mocking you with remnants of toilet paper.  You would yell out for another roll, but you're at your boss's house warming party with twenty of your "closest" colleagues. Conundrum.

This might be a common situation during the likes of a toilet paper shortage, an unthinkable reality in today's day and age. Believe it or not, a toilet paper shortage did occur in the USA in 1973! It all started because of a little joke on the Johnny Carson Tonight Show. After hearing about the government falling behind in getting bids for toilet paper from congressional representative Harold Froehlich, the writers decided to twist it to the extreme. On December 19, 1973, Carson's monologue read: "You know what's disappearing from the supermarket shelves? Toilet paper. There's an acute shortage of toilet paper in the United States."  

Surprisingly, the monologue set off a frenzy of toilet paper purchases the next morning with families stocking up on toilet paper to supply their foreseeable futures. On the afternoon of December 20, 1973 almost every store in the USA was completely out of toilet paper. America had artificially created the largest toilet paper shortage in its history.

Later in the week, Johnny Carson retracted his statement and apologized to America. But because shelves were already empty of toilet paper, whenever there were rolls available, customers would purchase all of it. The shortage continued for another three weeks until shelves were stocked again.  

This little history gem gives us an excellent example of consumer behavior in the face of a percieved or propogated belief and how dangerous un-vetted information can be. 

Reference:

The Johnny Carson Effect