Airline fees are scheduled to be a key topic at a Department of Transportation meeting Tuesday. Flyer aggravation about the fees is growing as they increase. Carriers now make billions in fees, more than ever before.

When it comes to fees, there are two extremes among U.S. carriers: the bold and the old. The bold includes airlines like Spirit, which piles on charges, even for carry-on bags. The old are legacy carriers like United, American and Delta, which have historically been less aggressive. But these days, the older are getting bolder.

“They’re charging for damn near everything that they can think of,” says Richard Gritta, professor of finance and transportation at University of Portland.

Transportation Department stats show revenue from baggage and change fees alone up 372 percent between 2007 and 2014. And that doesn’t even include money made on seat selection and food sales.

These fees are part of why airline stocks are doing better lately. Despite passenger protests, they are here to stay. And with all the airline mergers of recent years, there are fewer places to shop around.