I'm pretty sure people are panic buying just because other people are panic buying.
In December 1973, Johnny Carson joked on Tonight about an alleged shortage of toilet paper. Viewers believed the story and panic buying and hoarding ensued across the United States as consumers emptied stores, causing a real shortage that lasted for weeks. Stores and toilet paper manufacturers had to ration supplies until the panic ended. Carson apologized in January 1974 for the incident, which became what The New York Times called a "classic study" of how rumors spread.
Everything old is new again
