American Airlines recently announced record net profits of $7.6 billion for 2015, a whisker below trebling the prior year. Others in the billionaires club: Delta, United and Southwest, which topped the billion dollar mark for the first time ever.

A big reason is cheap oil, which means cheaper jet fuel. How cheap? In the summer of 2008, oil was closing in on $150 a barrel; by early 2012, it was just over $100. As of this writing, it hovers around $30 a barrel. (See A Complex Story: Global Impact of Low Oil Prices.)

Yet the old airline fuel surcharges remain. Oh, they don't call them that anymore; American Airlines refers to this extra on Europe fares as "carrier-imposed fees," while Delta's moniker is "carrier-imposed international surcharge." Any way you slice it, both airlines were charging $450+ per ticket for this fee last month though the real eye-opener was the base fare for a New York-London flight – a single dollar. Don't get excited; we don't ding our credit cards for base fares but for the total cost of a ticket, which includes that $450+ surcharge plus other taxes and fees.

Bottom line: Fuel savings have helped airlines become rich, but this has not trickled down to passengers. In fact as of the first of this year, average prices on U.S. fares were up about one percent over 2015. The question is, why are airlines keeping prices high?

Easy. It's because they can.

Let's face it, demand for travel at current prices is good. Not that airlines are satisfied with that. They are constantly probing demand by launching airfare hikes to see if we'll pay even more (there was a successful hike in the first week of January). Of course, if ticket buying slacks off, so will prices. In other words, airlines want to fly planes with every seat filled and every passenger paying the most money possible. Because they've gotten so good at controlling capacity and pricing, it's working.

In fairness to the industry, airlines don't always make money. Not long ago, they were in terrible shape following the one-two punch of 9/11 and the recession/depression of 2008/2009. Many airlines went out of business (remember Aloha, Skybus, ATA?) while others disappeared into mergers (Delta/Northwest, United/Continental, American/US Airways). This is when meals began to disappear and baggage fees materialized.

And no, fees won't disappear any more than prices will drop, and prices won't drop unless passengers tell airlines they can no longer afford to fly and that's not happening. On the other hand, there is some good news, but don't get too excited: American and United are bringing back free snacks in coach.

(See what you'll actually get to eat: American Airlines: Free Snacks in Coach.)

Rick Seaney is the CEO and cofounder of FareCompare.

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