This is not as unusual as it ought to be. I think there is a message in the small print somewhere that tells you to take the card with you - even if it has expired.
Both my wife and I have been asked for the original credit cards on flights we did not book and pay for but where the reservation was made in the name of the flyer. I have been asked once on a flight I did book and pay for where the credit card had expired. Every time it has been suggested I might have to pay again but they have also said that if I can subsequently show I have paid the second payment will be refunded. In every case, after an extended period watching the check in agent tapping away whilst wearing a worried frown the problem has solved itself.
Last edited by SLF3; 12th Feb 2013 at 08:01.