You should take this issue (which is all about fairness) up with the DOT; unfortunately the credit card company is stuck in the middle.
Several people, including myself, already have (see the thread
Telephone Ticketing Fee --> Increased to $25 ), and the DOT has already started asking around for examples of this practice. Your real-life example would be a great addition to the ones they have already received.
Let you thoughts known at
http://airconsumer.ost.dot.gov/escomplaint/es.cfm. I urged the Secretary to exercise his duty under
49 U.S.C. 41712 "Unfair and Deceptive Trade Practices" and cause AA to stop charging for transactions that AA does not allow to take place for free online. Incidentally, the DOT just did this in the case of AA involuntary denied boarding vouchers (same issue--they couldn't be redeemed online so were subject to the fee, something that the DOT termed an unfair practice, asked AA to stop, and fined AA for having instituted the unfair practice in the first place).