Answer:
When you rent a car, you drive away with a valuable asset. The rental car company wants to have recourse if you damage it or fail to return it. Rental car companies would rather that you pay for a rental with a credit card because it reassures them that:
You’re an actual person with a real identity. The credit card company has already vetted you.
You will be able to pay for the rental and for any damages that might happen.
The rental company trusts renters with good credit scores. A financial institution trusted you with unsecured credit.
You will return the vehicle because you want the hold and deposit on your card returned to you,
If you pay for a rental car with a debit card and don’t return the car, the rental car company might have more difficulty recovering funds from you. Rent with a credit card, and it’s more likely that the company can track you down and get its money back.