Despite the name, many people use "credit cards" simply for rewards and enhanced purchase protections, with only incidental use of the credit facility.
In the US market, it is surprising that someone would choose to use a debit card over a credit card (if they have the choice) because they are giving up the rewards and enhanced purchase protections, which are available at effectively zero cost.
If I used a debit card over a credit card, I'd effectively be paying ~2% more for most things I buy, for no benefit.