If you think it about this way, the greatest generation never used credit. They saved until they had the money to buy stuff. My grandparents never had credit cards, and it wasn't until my parents were in their 40's and quite wealthy before they started using credit cards.
If anything, you should use them only to maintain your credit rating. Keep a small balance (under $100) and use them to make small purchases. That way, you can reap the benefits to your credit score, without putting yourself in a huge hole.