I know that I've posted this all before, but good advice bears repetition. In the words of Bob Dylan, "Money doesn't talk. It swears!" Cash saves your life ( and maybe your wallet too) in a mugging. Cash buys you a ride/ flight/ train ride / hitch out of town, when all seats are booked or otherwise unavailable. Cash buys supplies in a blackout when all credit cards are useless. Cash gets you the unavailable hotel room in the blizzard. Etc. etc. In an urban setting you can break it up: wallet, bag, sock, hat, car, whatever. Your target goal is $500, minimum: 4x$50; 10x$20; 9x$10; 10x$1.00. More is better.

P.S. Cash can often get you a discount on a larger purchase. Offer your credit card for payment. An Am Ex is best because it's fees are largest. Then say to the proprietor , " Do you discount for cash?" Do not be surprised to save yourself up to 10%.

P.P.S. Do you remember the Indo-China ( Vietnam) war? In the early days especially, many Special Forces soldiers, CIA agents and Air America pilots wore Rolex Submariners and ~10 thin gold bracelets, for trade / bribery in an E&E situation. In fact the Rolex became something of a joking way to ID the CIA types. That watch and the infamous "Get out of jail free" ID card.