Barring a law outlawing them — or severely limiting them — fees for everything from checked bags, to food, to in-flight entertainment, to preferred seating, to early boarding (and possibly early deplaning) are hear to stay. But a new report from staffers on the Senate Commerce Committee claims that airlines may be going too far in trying to hide some of these add-on costs.

In 2014, commercial airlines in the U.S. made more than $3.5 billion from baggage fees, compared to $464 million in 2007, before the current fee trend began.

Another $2.98 billion in fee revenue came from reservation change/cancellation fees, that’s more than three times 2007 total of $915 million.

In addition to more airlines charging for all checked bags (Southwest now being the only major domestic carrier that does not), these fees have increased since their introduction, by upwards of 67% since 2009. Fees have also increased by anywhere from 40% to 100% for passengers’ second checked bag during these years.

Likewise, cancellation/change fees have gone up, now ranging anywhere from $60 to $1,000. According to the report, between 2009 and 2014, these fees increased by as much as 66%. Even on the lower end of fee increases, where they only jumped by 33%, that’s still several times the rate of inflation (10.3%) during these years.

Making matters worse is that — unlike most other ancillary fees — travelers can’t opt in or out of change/cancellation charges.

And yet, contends the report, the price charged for changing or canceling tickets often bears “little to no relation to the actual cost incurred by the airline when a ticket is changed or cancelled.”

“Airlines justify their change/cancellation fees by claiming the fees are necessary to cover the opportunity cost of an airline not being able to rebook a seat,” reads the report. “This rationale, however, fails to account for why many airlines charge the same penalty fees regardless of the lead time a passenger provides for an airline to resell the ticket.”

United, Delta, American, Hawaiian, and Spirit airlines all charge travelers a flat fee for a changing or canceling a ticket. The fee does not vary based on lead time before the scheduled flight. There are airlines, like JetBlue and Alaska, that do base the maximum charge for a change or cancellation on the proximity on the calendar to departure.

The report also takes issue with the idea that these fees are intended to deter consumers from changing travel plans on a whim. The report argues that if deterrence is indeed the rationale, “airlines should strive to provide consumers with clear notice of the potential for substantial penalties should they wish to change their plans.”

But, claim the senators, their review of seven different airline website shows that “consumers do not generally receive prominent disclosures regarding these fees when procuring airfare.”

Rather than prominently displaying these fees, the reports says they are usually found on a page separate from the listed airfares, written in small type under generic headers like “fare rules,” “fare restrictions,” “optional services,” and “optional fees.”

The report calls out United.com for being particularly confusing.

First, you pick your itinerary. Then on the next page, there is a small link to a page called “taxes and fees.”

Clicking on that link brings up a page that lists certain fees for ticketing but does not include change/cancellation fees.

No, you have to then click the link for “charges for baggage or optional services,” which then brings up another screen providing detailed info on baggage fees and a whole host of other charges. In fact, we had to scroll down four pages to get to the one small item that reads “Other flight changes and cancellations,” which only states that fees range “From $0 to $1,000 per passenger, based on applicable fare rules.”

It’s only after you select your flights and get to the “Review Trip Itinerary” page that you get the tiny link, included among others, where you can “View Rules and Restrictions.”

The text on the resulting page takes up more than 40 screens on your typical laptop. Beyond that, the rules provide no actual dollar amount for the penalty for changing or canceling your flights, only confusing details written in English, but not in plain English.

Another transparency issue involves passengers who go online to pick their seat only to find that the only available seats are so-called “premium” seats that come with a surcharge, often because they provide slightly more legroom.

While some airlines, like JetBlue, include a notice on their website explaining that passengers presented with only premium seating can skip this portion of the process and will be given a free seat at the gate, others make no mention of this option. Thus, some travelers are paying for premium seats they don’t want and don’t need to pay for.

“The traveling public is being nickel-and-dimed to death,” said Sen. Bill Nelson of Florida. “What’s worse is that many flyers don’t learn about the actual cost of their travel until it’s too late.”

Nelson said he intends to press his colleagues to act on the report’s recommendations when the Senate begins its work on legislation reauthorizing the Federal Aviation Administration.

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