Originally Posted by FlightWhite

Regarding the ultimate point: most people seem to be saying that because other legacy carriers have similarly priced redeposit fees, this renders this in some way fair... but what United does says nothing about AA's practice. The essential question isn't whether this is the rule (it is) or whether this is industry norm (it is). The question is whether this industry norm is fair.

I'd submit the answer is no. One camp would argue that since this is indeed a ticket, paid for in an alternative "pseudo-currency", then the airline is actually losing access to revenue when a ticket is cancelled, and so just like normal nonrefundable tickets they can charge for a cancellation. The difference here is that the miles are captive assets, and can only be redeemed on AA, and so are worthless in the open market. They are already "on the books" with AA. So it is more like a change fee: your money (miles) are with us, and still with us, and you pay for the pleasure of finding a different way to ensure we get them. If you view mileage awards as tickets, paid for in miles, then this reading works: you pay a change fee and can use the balance of your ticket (the miles) any way you want (i.e. with more miles, etc). The change fee/voucher system is in place to ensure your money stays with AA.