There are some people who literally just shop for what they need from week to week. Then when something like this happens, and they can't get out of the house, they run out.
This happened to me when I lived in Pennsylvania. We got a big snow storm. Then on the third day, it all turned to sleet all day long. Trees were uprooted and power lines came down all over the place. They had to shut down roads, and you couldn't get out for school or work let alone shopping; but I always have a warehouse of food, supplies, and water--can't run out!LOL
Fortunately, the electric company for that area was big and had more than enough crews to send out to make the repairs. We were without power for just three days. If we lived further into Pennsylvania, the boon docks, I'm sure it would have been longer.