If someone's got 400,000 miles due to expire and it's a choice between $4,000 and the possibility of losing them, the person might take the money. If he gets caught, he was going to lose the miles anyway.
If US Airways survives, as that date gets closer, you can pay your $40 and put the miles back in your US Airways account, ... If they don't make it, you've got something you can use that far out. It might be better than having nothing at all.