Actually, the BANKS have system in place to catch large amount of refund that did NOT have prior charge(s) to match it.

The story went like this: someone paid ahead a year's worth of Cable TV subscription with different credit cards back in the old days when spending requirement to earn sign up bonus was a measly $250... Then he called the cable company to ask for a refund... After a few of such attempts, the cable company decided to refund all the advance payments to ONE single card, being the last card used to pay for the bill, but needless to say, the amount refunded was much larger than the payment(s) made by this card...

Long story short, the card issuer froze the refund. I only learned the part of the story up to that point, and never was told the final outcome of it... despite I asked the person a few times... I could only guess the outcome might not be good...

Dont let your creative juice run wild, for you never know what is put in place to spot fraud activities as seen by the software...

Expedia once issued a courtesy credit to me that was considered a compensation for my not taking them up on a hotel price error (6 nights in Hilton Tokyo at 1/10th of the normal rate.) The supervisor told me they had a special code to use for credit back to CC WITHOUT prior charge in order to make the credit go through. Now I have no idea what he is talking about, but come to think about that, this obviously also has something to do about the refund must go back to the original form of payment.