When this whole system was introduced with e-ticketing etc, one of the FAQ's Tony T'lier came out with was that they had the option of creating the software that would
A: Not billing you if you are bumped up a class carrying a lower class ticket, but also not billing you for a lower class if you were bumped down
or
B: Billing you for the class you flew in regardless of the ticket you presented
Tony (obviously looking after our best interest) said they chose option B
Number of times traveled on CX subload - Hundreds
Number of times bumped down to EY, J Seat, Crew Seat with a J/F ticket - Tens
Number of times bumped up a class - Zero
Having CX look out for staff - Priceless