Sometimes you need to make a small payment in a foreign currency and credit cards aren't an alternative -- Canadian income taxes, for instance. U.S. banks will charge anywhere from US$25 up to issue a check on a foreign correspondent bank.

Or you can go to the AmEx office and buy CA$280 of travelers checques at no fee (if you're an AX cardholder, and who in this forum is not?). Make them payable to the Receiver General, sign in both places, and mail.