It's one of my pet peeves about how some banks deal with Visa Debit cards.

Apparently Visa treat getting foreign currency as an overseas transaction and charge a premium to the banks and some (most) banks pass that on to customers.

RBS / Nat West have just moved everybody from Maestro to Visa Debit and are imposing the charge and have lost my business due to it. Nationwide and HSBC are two banks that don't pass on any surcharge.

RBS's answer by the way was to get cash out of the bank to pay for the currency if you want to avoid the charge which is a bit challenging if you're pre-ordering over t'internet.