Maybe he's paranoid about giving out debit card details online?

Personally, I'll never understand the concerns. The only way you'll get screwed over is by entering your full card details on dodgy or fake websites. Most business are covered by a ton of security layers, and will refund you in the unlikely event that something does go south. There's also countless fraud detections being undertaken by modern banks, so again there's very little concern on that front either, and when there is they're swiftly dealt with.

There are plenty of payment options available no matter which portion of the globe you reside on. It's your decision on whether or not you want to use them.