Although most adults have credit cards, millionaires are even more likely to use them. Dig deeper: Best credit cards for 20256 reasons why millionaires use credit cardsMillionaires use credit cards thanks to the convenience and perks they provide. They earn valuable credit card rewardsMillionaires earn valuable rewards by using credit cards, from paying for groceries to buying clothing. They get card protections and insurance coverageMillionaires use credit cards because many credit cards automatically give you added protection and coverage. Read more: How to transition your spending from a debit to a credit cardFAQs about millionaires using credit cardsWhich credit card do rich people use?