US banks make the same promises too.

But which would you trust more when something goes wrong and your "card number" racks up thousands of stolen purchases:

1) credit card dispute/chargeback process that is mandated by law

2) the promise from your bank that, on their good will, they will fix things

Not only that, but thousands of dollars on your credit card is "loaned" to you by the bank, the money's not out of pocket on you yet.

However, thousands of dollars of stolen debit card transactions means your bank account is thousands of dollars lower immediately, and you have to hope your banks promise to give it back will actually pan out.