I always use my credit card when I shop. I don't like carrying a lot of cash around and we get 2% cash back on all purchases which is nice. We pay the bill in full @ the end of the month anyway, my DH is a CPA and financial advisor so no chance of getting into any trouble!
Yes. We use a cashback rewards card and charge almost everything (anything we can) on it. Then we pay it off in full each month. This way, we never pay a dime in interest and we make thousands of dollars on the cashback money.