Wow, that is harsh. I was on hubby's account before I came here to live permanently, but then again, that pre-9/11 and the new money laundering rules.
For those that are using their spouse's card, be aware that you run the risk of 'clued-up' retailers retaining your card, particularly as some cards have the Mr/Mrs distinction (red flag!). At one time, they were running a £50 reward per captured card as an incentive to checkout staff to be on the ball. If your card is captured, your bank will be notified and there is a risk that your spouse can lose their account because allowing someone else to use their card and pin is a violation of banks' terms and conditions. It could also lead to further trouble down the road if your spouse's card is stolen or has other fraudulent issues.
Just something to keep in mind.