Image: Airport check-in (© Corbis)
Meet the man behind one of the most reviled moves of the airline industry: 54-year-old John Thomas, the airline consultant who devised the checked luggage fee.

Thomas' idea may have saved some airlines from insolvency, but it has also set off grumbling among the roughly 732 million people who fly commercially in the U.S. each year.

But luggage fees aren't something that Thomas himself deals with. That's because he flies on a seven-passenger Cessna Citation jet, according to The Boston Globe. If Thomas has to travel on a commercial airline, he uses only a carry-on, bypassing the checked-luggage fees. 

"Oops," he told the Globe, when the publication pointed out the irony to him. Thomas said he learned to fly after high school and started a small airline while a university student in Australia.

Thomas' notion is credited with generating $3 billion a year for the airlines, money that has helped keep some companies aloft. He first came up with the idea in 2006 for a Canadian airline, then trotted out the plan when a U.S. airline, which Thomas said he couldn't identify, was searching for new revenue streams. 

Then in 2008, United Continental's (UAL) United Airlines said it would charge $25 for passengers' second checked bag. Soon, US Airways (LCC) and almost all other major airlines followed suit. 

"I would credit bag fees with saving the industry that year," Jay Sorensen, president of travel consulting firm IdeaWorksCompany, told The Globe. 

While it may have saved the airlines, it's one reason why consumers increasingly hate flying. Passenger satisfaction dropped last year, with travelers vexed about checked bag fees, according to J.D. Power

Thomas, who works for London-based consulting firm LEK Consulting, isn't done yet with drumming up new revenue ideas for the airlines. Want an empty seat next to yours? Pay $100. That's one option Thomas has advised a British airline about. He also has an idea for gambling with frequent-flier miles, given that online gambling regulations are being loosened. 

"Think of it as being in the mall with nothing to do, and there's a blizzard outside, so you're stuck in the mall for five hours." he told The Globe. "That’s probably worth another $5 billion."

Follow Aimee Picchi on Twitter at @aimeepicchi

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