I'm not a lawyer, so this is by no means complete. But the only thing similiar to anti-hoarding laws I can think of are the "price gouging" laws that many areas have. In florida, it goes something like "Gas / Food / Hotel rooms can't sell for more than their average price in the last 90 days". Which prevents gas from going to $10 a gallon and rooms to $300 overnight.

I'm curious if there are any anti-hoarding laws which apply to individuals. And note the price gouging laws only seem to control how much you can sell something for, not how much of it you can posess.

My guess would be that anti-hoarding laws would spring into existence instantly in the event of a real shortage. But enforcing them would be interesting. If you've purchased your supplies early, paid cash and kept quiet about having them, then how will the authorities know?