Originally Posted by J.Edward

At the end of the day any corporation who has to face a jury will have tremendous pause due to the inherent risk in doing so.

However many "normal" citizens are emplaned will carry their unknown biases, prejudices, beliefs, etc. which will be used to articulate the jury's verdict. There's no way to know these in advance and jury selection can only weed out the obviously biased potential jurors. Point is even if the law is blatantly on UA's side, a jury can STILL tell the airline to pound sand - think back to the northern juries pre civil way who refused to convict those who aided runaway slaves if you're looking for a dramatic example of this in action.

If it becomes precedent that UA (or any carrier) cannot enforce an unconscionable aspect of the Contract of Carriage - i.e. FORCING a customer to take a flight - it kicks out a major component of how airlines sell and price their fares. Moreover, it also opens the door for lawsuits against the carrier for retributions taken against customers. UA closed my account for hidden city ticketing? That's not fair! The entire concept of "hidden city ticketing" is unconscionable therefore it is also unconscionable for UA to take any negative action against me! AND if a sanction or closure of a M+ account goes to a jury the law might again be on UA's side but the jury might STILL decide against UA and blow a massive hole in the concept of loyalty accounts are the property of the issuer and can be changed/closed at the issuer's whim.

Anyways the tl;dr of this is litigation is fraught with peril. If UA loses the entire industry may be dealt a serious blow and even if UA "wins" they can still lose in the long run.