I have to go with Selco on the cash. Doubt it would be worth nothing during SHTF. Say you are trying to get out of town and you just brough the last ten gallons of gas at a station and there’s no telling when they will get resupplied, how much is that gasoline worth?
That's why it's good to have a high mpg Diesel car and a (portable) stash at home.
Who is Selco?
The reason you want cash is that paper money and coinage only make up 10% of the money supply, the rest being digital. For sure the digital money will disappear, but people will be hungry for cash and coin - there won’t be any debit cards, checks or credit cards.