In a country scale crisis people would be selling all their valuables for fire sale prices to pay for essentials, including gold. A fiat reserve currency, like the Swiss Franc or the Pound would be easier to use, less likely to be stolen and more valuable then gold shavings.
Gold isn't going to save you from a zombie apocalypse, nor can you eat it.
It will however transport your wealth from one side of a currency crisis to the other while retaining value - as opposed to plastic notes with arbitrary numbers of zeros printed on them.