Well laws exist to protect both consumers and producers (AA). AA quite blatantly violated laws, DOT regulations, and their own commitment to costumers.

It does not matter if you sign a bad contract, it is legally binding; thus you must follow through with your end of the deal. If you fail to do so, you will be sued and ordered to reimburse those affected by as much as treble damages. Airlines that violate DOT rules are regularly slapped with large fines and Cease & Diciest notices.

Furthermore, if AA forms a pattern of violations, or disregards DOT's rulings and laws, they could be liable to loose their certificate of operation.