In the wake of Hurricane 'Iwa in '82 (only a Cat 1, but it ravaged the islands) this was definitely the case. Our area was really whacked with the storm surge and flooding, but a few miles down the coast, hardware stores and restaurants opened a day after the event despite having no power. They were selling off-menu stuff like cold cut sandwiches. I remember a chain burger joint whose owners had brought their personal grills.

Looking back I'll say it was probably just as good psychologically as economically for the business owners. There's something to be said for inserting a bit of normalcy into a disaster.