It's less that silver has "redeemable value" and more that "what the fuck am I supposed to do with this rectangular piece of green paper when all the banks and the nation that support it are falling apart..."

Think of silver and gold less like buying silver and more like reducing the risk associated with holding only USD. It's a way to protect part of your savings from utter collapse, so that you have something to restart a new life with in a new society that emerges from the ashes.