most people over 18 do have a credit card and or debit card. it is very rare to use actual cash now due to all the stores and such are computerized, digital scanning. not saying people dont still use cash because some do, just that many stores, community agencies like city bus lines, air ports, train stations,DMV, social security and others now require payment by credit or debit cards. many USA states now also require everyone over 16 to have either a drivers license or state ID issued from the department of motor vehicles.

there are also many states that have changed their social services (ie food stamps, money and medical insurance plans) over to a benefit card that gets scanned rather than paper.

the enjoyment of living in the computerized digital age, paper is on the decline and "cards" with a security chip are in.

I do have to say carrying a debit card and credit card and photo ID is so much easier to deal with then standing in line counting out paper and coins.