"The amount of money that's involved is steadily increasing, and that may change some minds on the Hill," Dillingham said. "In my opinion, if that number continues to grow, the interest in having some of those funds be available to the aviation trust fund would also grow."
Whether the fees become a tax target when Congress next takes up aviation funding may depend in part on the stability of the airline industry. Already heavily taxed on tickets and fuel, and saddled with numerous fees, the airlines will underscore that they contribute an estimated $1 trillion in economic activity each year and employ almost 10 million people.
Medina points out that they lost $55 billion and 150,000 workers in the first decade of this century.
The squeeze to escape baggage fees by loading up the carry-on luggage has been blamed for longer lines at airport security checkpoints and occasional delays when every available nook in the cabin has been crammed full without finding room for it all.
Two airlines, Spirit and Allegiant, have begun charging passengers for some carry-on bags, too.
For some travelers, the fees are the cost of convenience.
Craig Furuta's job has him flying all over the country, and says he sometimes brings home more baggage that he left with if he finds things that he can't get in Washington.
"Such as, I bought a suit in London that I couldn't get here in the States, or buying certain jams and jellies — the local stuff is always the best stuff," Furuta said.
He had to lay out additional cash recently to check an overweight bag on US Airways.
"I was flying from Orlando, and I had it overweight because it was packed with souvenirs from Disney," he said. "It was $50 and it was worth it."