Defending his airline's fees today, Baldanza said that without them, he wouldn't be able to keep base airfare prices so low. He also said Spirit had such a high percentage because its fares were so much lower than the other airlines.
"The primary reason for the carry-on charge was to reduce the amount of baggage brought into the cabin," he added." Carry-on bags have become a nightmare for passenger boarding and deplaning. They create a safety risk for both passengers and flight attendants and lead to costly flight delays."
In March, the Association of Flight Attendants reported that 80 percent of flight attendants had been injured during the last year by moving carry-on bags in and out of overhead bins.
Baldanza said Spirit doesn't just help its passengers with low fares, but "provides an important public interest service" by keeping other airlines in check.
"Spirit's impact was clearly demonstrated when its pilots went on strike last month and other carriers, including low fare carriers, immediately raised prices," Baldanza said. "For example, JetBlue raised its roundtrip fare in the Fort Lauderdale-San Juan, Puerto Rico market from under $200 to over $600."
Most airline experts don't see the fees going away anytime soon.
"Airlines have become addicted to fees in the same way that state government has become addicted to cigarette taxes," George Hobica, president of airfarewatchdog.com, recently told ABC News. "I don't see them going away anytime soon, if ever. They spell the difference between insolvency (as in ceasing to fly) and merely losing billions of dollars."
But what really alarms many is the rate at which those fees are climbing.
Last year, U.S. airlines took in more than $7.8 billion in fees from passengers, according to the DOT's Bureau of Transportation Statistics. But in the last three months of 2009, the airlines charged passengers $1.9 billion in extra fees, up a whopping 18.3 percent from the same period the prior year.
That is why the DOT, under the leadership of Transportation Secretary Ray LaHood, has taken a more active role and proposed the new rules.
The flying public often lacks a "clear and adequate disclosure of these fees by airlines" and are unable to determine the true cost of their ticket prior to purchase, the DOT's general counsel, Robert S. Rivkin, told Congress today.
The General Accounting Office released a 50-page report today on all of the fees. It includes a comprehensive list of all the fees imposed by airlines for optional services.
"While the general concept of unbundling airline services gives consumers the option to pay for only the components they want, at least in theory, many airlines have crossed the line when it comes to ancillary fees," Anne Banas, executive editor of travel Web site SmarterTravel told ABC News. "As a result, it has become extremely difficult for consumers to effectively compare prices and make informed choices when purchasing a fare, and airlines have been taking advantage of that fact, especially by not disclosing fees appropriately."
Not all airlines think fees are necessarily.
Dave Ridley, senior vice president of marketing and revenue management at Southwest Airlines, told the House Committee on Transportation and Infrastructure's Subcommittee on Aviation today that his airline refuses to "nickel and dime" passengers.