The banks have done a wonderful job convincing customers that debit cards are so convenient that it's worth paying a fee everytime they use one.
You don't pay a fee, you say? If you deal with a major bank, you probably pay for a monthly service package, or you avoid the service fee by maintainjng a required minimum balance. In either case, you are still paying.
While debit cards do offer the convenience of paying for your purchases immediately without having to carry cash, so do credit cards. And credit cards have the added advantages of no transaction fees for the user and payment that is not due for 20 or 30 days. Given that you can buy almost anything today with a credit card, there just doesn't seem to be a good reason for using that debit card.