As I said, not a popular opinion at this time in our culture. Perhaps I should have been more clear. Yes, credit cards can be a useful tool when used responsibly and if you have a great amount of self-control. I admit, if you travel more than once a year or fly, credit cards are pretty much a necessity, especially if you rely on company reimbursement for expenses.
The reason I put this out to think about is that it can become easy to charge up a good chunk of money and all it takes is one unplanned event and you might have thousands of dollars sitting on a credit card with 10%-18% interest. This can particularly happen when furnishing your first apartment/house or starting a family. This can also easily happen if you carry your credit cards with you and see something that is a great bargain or something you really "need". If you are forced to think about it some more before you buy, you may find that it is not such a great bargain, or you don't really need it.
Debit cards serve the same purpose of credit cards, except it comes directly from your checking so you have to have the money to pay for something. Makes you think a little harder before you purchase something...and you pay no interest.
I have not had a "general" credit card for several years, and everytime I need a loan, I am greeted with "wow, you have excellent credit! I've never seen a score that high." I do maintain a credit account with a national home improvement chain to help keep my credit history current. In addition, I have built a relationship with my local bank and credit union for home and car loans. I pay loans off early. You do not need several credit cards to maintain a credit history.
If you must keep credit cards, do not carry them with you unless you plan to purchase something ahead of time. If you absolutely must carry a card, set the limit low enough it can easily be paid off every month, even if an emergency comes up that requires extra cash (more common than you want if you own a car or house).
I agree with those who say the key is discipline. I'm just trying to provide some insight, discipline isn't always enough and that's where the troubles start. redkardz, you said yourself your parents were in credit card debt until just recently. I imagine that created some tense moments in your household, I know it did for my parents. I try to prevent that for my children. If you are disciplined enough and responsible to pay off your credit cards every month,then by all means go for it. Most people are not, however, over the long term. Lastly, if you know anyone who is financially independent ask them if they got there by using their credit card rewards or 0% interest for 6 months, or auto bill-pay to save postage?