We've always kept enough food in for a couple of weeks, just seems easier. If something is not available (very rare so far, apart from the height of the pandemic when everyone went mad...) we just get something else.
I do know people who seem to shop every day, for that days food, I find that a bit weird really but each to their own.
I don't particularly remember a time when the gas supply went off, unlike electricity, so for that reason we have a gas hob.
Also, the usual camping gas canisters and cooker if the **** really did hit the fan. Even then I don't believe it would be for long.