And, of course, people aren't going to stop wanting to get drunk just because they can't pop over to the corner bodega for a six pack whenever the urge strikes. Portability and long shelf-life make liquor of all types a valuable trade good -- people will kill to get a taste of the delicious bottom-shelf leftovers from your local dive bar when their only other option is the equivalent of prison wine.
Earthquakes, tornadoes, and hurricanes can cause you to leave your home or even be trapped there. Roads could be blocked due to fallen trees, power lines, or even damaged earth from the natural disaster. Rescue crews can not be in all places at once. You may have to wait it out for quite a while before its over. You won't be able to go to the store or to the corner market.