I've never understood how an industry so hard for competition to get into, so defensively positioned with regulatory capture, and so overpriced and gouge-happy from a consumer PoV, can somehow manage to be barely scraping by. What is going on at the airlines where they seemingly can't make ends meet despite a silver platter cornered market?
Did you expect your $200-300 cross-country flight to really give much of a profit to airlines after airport taxes, landing fees, fuel, maintance costs plus labor, insurances and everything else?
Those flights should cost 10x as much if you want the golden treatment fliers received in the 60s.
Airlines are a great example of competition driving prices down for consumers.
The "gouging" is just to appeal to the truly cost sensitive; people with no brand loyalty, time constraints, etc. If you don't want a soda, a checked bag, a seat assignment, and the option to choose from 10 different times of day to leave... but do want $50 in cash... they have you covered. It rubs people the wrong way, but people "sort by lowest price first", not by "lowest hassle first", so they have to account for that somehow. (Tangent: I never really understood this. I feel like air travel would be way smoother if people checked their bags instead of fought each other for overhead bin space. They should charge for the bins, not for the cargo hold. But I guess that's too hard in practice.)
If you had an airline that just charged actual cost + desired profit for a certain load factor, the ticket would be $1000. Then someone else would show up and charge $999 because they can pay for a slightly less well-trained flight attendant. Then someone else comes along and puts the rows of seats 1" closer together. Eventually the price is what we pay today, because all that actually happened. I think the industry is so hyper-optimized that it's basically "free" to fly; you're just paying for transport at cost, or even less than cost if they have done their yield management correctly and you got the lowest fare on the flight. That's why the industry is so sensitive to disruptions -- it's balancing on a razor thin margin, because there are competitors ready to make $1 less to get your butt in their seat.
Anyway, I think your assertion about a silver platter cornered market is simply wrong. Flying is ridiculously inexpensive compared to the costs. As a comparison, get your ATP certification, buy a 737, and fly your friends around in it. Pretty expensive compared to a ticket on Southwest!
What about in-flight food and alcohol? In-flight wifi/movies/media? Does Sky Mall pay a commission? I'd be curious how much all of those things add in revenue after the door closes.
But there is a lot of competition; wikipedia lists 10 major (doing $1B annually) US 'mainline' passenger airlines, and three more major regionals (although one is a subsidiary of a mainline). It's hard to stay non-competitive with 11 other big companies doing the same things as you; especially when non-majors can compete too.
That's not to say there's no gouging, there is a lot of opaque pricing and nickle and diming. But, if your route is served by multiple carriers, there's probably not a lot of consistent profit there. If you're flying out of a small airport that does two flights a day and the nearest airport is a 4 hour drive, there may be some more profit there, but it depends on utilization.