Here's what I don't understand about you debit card users: sure, you may have the funds right now in your account, but what about the bills that are still to come before your next paycheck? See, I can't keep track of that any easier than I can my credit card spending!
I get paid twice a month, DH gets paid once. The bills are due all over the place, not just at the end of the month. Not all of our bills can be paid online, so I frequently have outstanding checks that haven't cleared the bank. I can't tell from the balance what has cleared and what hasn't and how much disposable cash I have. We have a mortgage and insurances that are automatically deducted, but the date can vary a little. I have been known to assume something has already been deducted, only to find out it hasn't! I absolutely will NOT overdraw my account or bounce a check, so when I need something for the house, or I get an unexpected expense that I can put on a credit card I will - at least that way if the money isn't sufficient to pay it all off one month I can take 2 months to do it. It rarely happens, but at least it can! If I make an error in my reckoning and end up spending more than I have, how do I replace that money??? Some other bill then has to suffer. And sometimes the cost of reconnecting a service (water, electricity, cable)that was cut off ends up being more than the interest I'd have paid on the remaining credit card balance!!
I guess I just find the credit card thing easier somehow.