Even taking a vacation may weigh more heavily on the pocketbooks of the obese, says George Hobica, founder of Airfarewatchdog.com, based in New York.
"Some airlines, such as JetBlue, (Southwest) and Air France, have policies that 'passengers of size' have to buy a second seat," he says.
The only break for an oversized passenger would come in the form of a refund if the airplane isn't full, says Hobica.
"Some smaller discount airlines, such as Spirit or AirTran," he says, "do have a few pretty cheap wider seats, but they are not upgrades and have no perks."
The average extra cost of these seats, he says, is $60 per leg of a trip.
"If the economy class is sold out, they could turn out to be less expensive," says Hobica. Another option on some airlines is to buy a last-minute upgrade to domestic first class, which has wider seats, he says.
Those who prefer to drive, according to the George Washington University report, pay more for gasoline -- up to $36 more per year than people of average weight.