Actually, that’s not 100% right. If the OP was on a UA marketed/operated flight UA would receive the entire revenue. Changing that to a AC marketed/operated flight would result in the loss of all the revenue. If it was changed to a UA marketed/AC operated flight AC would get all but like 3% of the revenue for that segment. The financing of code shares is very complicated and depends on the prorate fee but essentially if UA sells you a UA marketed flight and it is another operating carrier UA essentially only gets paid a "commission". I agree with one of the posters, with 55,000 employees who don't get paid very well you certainly get issues with people wanting to do their own thing and its not worth getting too worked up about. Also if the OP wanted to fly AC why didn't they just book AC? UA did lose revenue because they lost the fare and because you booked a seat a held it to DOD that they were not able to sell it to someone else.