I couldn't find any example of such a thing in this united airlines contract.
"> 5.6. A service charge may be payable by any passenger who:
> 5.6.1. fails to arrive for departure at the airport or any other point of departure by the time we have specified (or if no time has actually been specified, with insufficient time to permit completion of official formalities and departure procedures) and, as a consequence, does not use the seat for which a reservation has been made"
Also, the court literally found it to be in the contract.
If you have chosen a tariff that requires observance of a fixed ticket sequence, please note: if carriage is not used on all individual legs or not used in the sequence specified on the ticket with otherwise unchanged travel data, we will recalculate the airfare according to your altered routing. The airfare will thereby be determined in accordance with the fare you would have had to pay for your actual routing in your price group on the day of your booking. This fare may be higher or lower than the fare you originally paid.
If the price group you originally booked was not available for the altered routing on the day of the booking, the cheapest available former price group for your altered routing will be taken as the basis for the recalculation.
If on the day of the booking for your altered routing, a higher fare would have been determined, we will subsequently recover the difference taking into account the fare already paid. Please note that we can make carriage dependent on whether you have paid this difference in price.