Having a credit card and building credit is essential in the modern economy. I do advocate only using it to purchase items you have cash in hand for, or doing without until you do. Advocating responsible use of a credit card does not mean you advocate the holder going into debt.
As long as you pay off the bill on time every month, credit cards are smarter than cash. You can gain interest on the float and perks such as rebates for just using the card. Pay it off in full so you don't pay interest, and you're ahead.
