[danudey]

'Don't forget in the UK the vast majority of purchases are Chip+PIN only, so a credit card number is only really useful for making online purchases from other countries, which are usually scrutinized far more by banks.'

It's true. A friend of mine moved to Canada from the UK with tickets bought on her card, changed her credit card's billing address to Vancouver, and called the card issuer to let them know she would be moving.

Immediately after she made her first purchase in Canada, they put a hold on her card. She had to call back to get the hold released, but it was put back on as soon as she made another purchase. This continued until she got a new (Canadian) card.

It's too bad the banks in the UK don't scrutinize themselves.