No it probably doesn't cost anymore but how would you do it??Oh now come on it is just greed, they have a captive audience and know they can sell ever seat at just about any price, it doesn't actually cost any more to run the flight.
It isn't scalable like a website, just growing and shrinking flights and attendants and pilots at a whim. They put out a price...you decide to fly then...or some other time...your choice. But again with so much demand and minimal supply...how would you do it?
You've got 10 beans a month to sell...you have your livelyhood based on selling these beans. Most of the time you can only sell eight beans...some of time you can only sell 6 or 7 beans...but one month everyone wants to buy beans...all your customers who only buy one bean every few months want one...and some that only buy that month want one...how do you decide who gets a bean?? Do you raise your prices that month?? Do you lower your prices other months...do you let folks that buy in advance have a discount?? That is what I would do...