To put a finer point on it: Imagine a disaster that seriously impacts food delivery for several days, e.g. while access roads are cleared of debris/snow/whatever. You want some reasonable mechanism that distributes food to people until normal operations can continue.
Given wealth distributions as they exist today - i.e., unequitable ones - using flexible prices may lead to a situation where sufficiently rich people maintain their eating habits to an extent where not enough food can be provided to the poor, who are then likely to suffer entirely unnecessary deaths.
An alternate system of explicit rationing, such as has been used during major wars, works better in such situations.
Equity of distribution doesn't strike me a particularly good metric for dealing with emergencies anyway since it's easily maximized by not letting anyone have anything, which is essentially what 'gouging' bans achieve.