> Price each ticket based on what it costs and a fair margin
That sounds great in theory, but airlines are the textbook example of "what it costs" not making sense. An airplane costs almost the same to fly from New York to San Francisco whether it's completely empty or completely full. The margin cost of fuel for your 150 lbs of body and 50 lbs of luggage is pennies compared to the cost to operate the airplane generally (e.g., a 777-300ER costs about $320 million today, or a lease payment of about $45,000 per DAY [1]... plus depreciation of the engines, maintenance, inspections, flight crew, cabin crew, etc).
How do you divide that up? If you assume 100% capacity on every flight, the airlines will be even broker than they already are (airlines are hardly raking in money: American Airlines filed for bankruptcy in 2011, Delta and Northwest in 2005, US Airways in 2004, United in 2002, and US Airways again in 2002...). [2]
If you assume something in the middle, maybe 70%, then you end up with a silly situation where seats are flying empty even though the airline would be happy to sell then for 50% off and people would be willing to fill them for 50% off.
Then add the fact that first class passengers are willing to subsidize the rest of the cabin... and so are people who need flexible fares, etc.
Airline seats are a lot like software in that there isn't a good way to figure out "charge what it costs." On average, we know the airlines are charging slightly LESS than what it costs to operate an airline. But it's not like gasoline where you can figure out how much it costs to refine a gallon and then charge a small markup.
[1] http://www.myairlease.com/resources/fleetstatus
[2] http://en.wikipedia.org/wiki/Airline_bankruptcies_in_the_Uni...