There really is no reason these days to carry any cash or transact in cash. Your salary gets paid into your bank account, too much effort to go to an ATM and draw cash if you can just pay by debit/credit card.
Since moving to Canada 2 years ago almost never have cash on me. So much so that I dont really know what it looks like or what is on the face of it. Everywhere you just tap your card, whether it is a shop or a street vendor everone has tap card machines. Takes 2 seconds, no waiting no need to enter a pin. No carguards or petrol attendants to give a tip to nor any beggars so no need for loose change.