To a certain degree, preemptive food hoarding is encouraged in disaster-prone areas. FEMA suggests keeping a two-week food supply on hand (see http://www.fema.gov/pdf/library/f&web.pdf ). In addition, every state and U.S. territory has stocks of commodity foods that include the National School Lunch Program, the Emergency Food Assistance Program, and the Food Distribution Program on Indian Reservations. In an emergency, USDA can authorize states to release these food stocks to disaster relief agencies to feed people at shelters and mass feeding sites. If a Presidential declaration occurs, states can, with USDA approval, distribute commodity foods directly to households (including the use of disaster food stamps) whenever normal commercial food supply channels such as grocery stores have been disrupted, damaged or destroyed. (see http://www.fns.usda.gov/fdd/programs/fd-disasters/ ).
Educating the public about disasters and disaster preparedness is one method of mitigating attempts to hoard after disasters strike.