You can use your debit card as a credit card by electing to sign for the purchase rather than put in your PIN. Also, many debit cards offer airline mileage plans tied to its use.
I haven't used a credit card in 5 years, have one, don't use it except to make reservations.
Bought my car with it 3 years ago and the bump up in mileage jacked my airline status to elite, which I've had ever since.
Much better than using the credit card.