I don't like debit cards as much for a few reasons:
1. Not very rewarding. The few that do, have somewhat poor rewards in comparison to credit cards.
2. Harder to fight stolen purchases. Credit card companies are better at this than banks.
3. More risk of an over-draft fee. If all your bills are paid at the same time, and you go out and buy groceries, you can dip quite low into your checking account's balance. If something goes wrong with your paycheck's deposit, you're in for some trouble. Some banks (like WAMU) waive the overdraft fee, but it isn't industry standard yet.
4. Less wealth building. I use an Orange Savings account, and it requires a few days to transfer money back and forth from my checking to my savings. Using my debit card would be a pain, as it would mean I would have to transfer out of the Orange account more often (and I rather like that 4.5%!).
However, your point is well taken. For those who aren't good at budgeting or controling themselves, debit cards are a savior.
