When I lived aboard the sailboat, I kept PM. This was largely for INTERNATIONAL use, incase of a dollar collapse while I was in another nation. I could se a use scenario similar to this:
Me: Hi, I'd like to rent dock space here for the next year, to let things bacn in the U.S. cool down.
Him: I'm sorry Senor, but we do not accept U.S. dollars any more, they are worthless.
Me: Producing a Canadian Maple Leaf in Gold "How about THIS?"
Him: Oh, Si Senor, that will work fine.
OTOH, for domestic emergencies when internet sales of bouillon and secure shipment to metal buyers is not available, not so much.
YMMV