In the United States checking/debit consumer protection is weaker. The legal minimum banks have to do depends on how quickly you notice a suspicious transaction. If you report it within two days your liability is capped at $50. If more than two days have passed your liability is $500. If more than 60 days have passed since the statement was sent fraud loss liability is unlimited.
When you go to file a fraud claim the bank must provide a provisional credit for the amount of the transaction but they may reverse this if they decide it was not fraud. It depends on what state you're in, if you used a branded (Visa/MC) debit card, the bank, the representative's interpretation of all the applicable rules, your prior chargeback history, etc.
With credit cards the legal maximum is $50. And the fraudulent transactions are drawn on a line of credit (soft money) not the contents of your bank account (hard money). The United States has a powerful oligopoly of payment network operators who lobby to maintain high interchange revenue. This de facto shifts the cost of credit cards onto those who don't have them. Instead of annual membership fees for the actual users, merchants pay about 2% of card transaction volume instead of 0.3% in the EU.
I forgot that credit cards comes with insurance in some places. Most apparent is that you can't even rent a car in some parts of US without a credit card. In EU that type of insurance may be included in the legally obligated housing insurance.
Really? In what cases can an average credit card user challenge a payment that has not already occurred?
If there is a fraud usually it is quick to get money back if debit cards were used.