As airlines charge extra for baggage while adding more fee-based amenities such as premium seating and Wi-Fi, it’s getting more difficult for travelers to compare the cost of a flight on different carriers.

A push for making comparison shopping easier could require airlines to share data on fares and fees with online travel agencies such as Expedia, Orbitz and Travelocity.

But airlines are resisting, saying they have the right to decide which companies they partner with for sales. While online travel agencies can help airlines push more tickets, the carriers also see them as middle­men that profit from the product sold by airlines — and drive fares down by intensifying competition.

“What’s happening is they’re blocking competition by blocking comparison,” said Kurt Ebenhoch, executive director of Air Travel Fairness, an advocacy group representing travel search companies.

While many travelers want to find the lowest fare, carriers such as Delta Air Lines don’t want to be compared with other carriers based solely on price. That, they fear, would result in a race to the bottom in fares.

Instead, Delta and other major carriers want to attract customers willing to pay more for more creature comforts, like extra legroom, Sky Clubs, in-flight Wi-Fi, power outlets and food or beverage options.

The U.S. Department of Transportation in 2016 under the Obama administration started a process to collect public comments on the issue and whether consumers are harmed when airlines restrict where their flights and prices are listed. The process attracted more than 58,400 comments, but was suspended by the Trump administration in 2017.

Ebenhoch hopes for movement with legislation introduced by Sen. Susan Collins, R-Maine, to lift the suspension. But he acknowledged that airlines “are exerting a great deal of pressure” to kill the measure.

Less regulation

What’s more, the Trump administration is looking to reduce regulations, not add more.

The DOT in December declined to impose regulations on airlines to increase transparency of baggage fees. The DOT cited its priorities and the priorities of the administration, along with Trump’s 2017 executive order to reduce regulation.

It’s a position that has benefited the airlines.

Airline lobbying group Airlines for America released a statement saying it believes that “dictating distribution and commercial practices to the airline industry would only benefit those third parties who receive a commission on sales through ticket distribution, and not the flying public.”

“Airlines ... need the freedom to determine which third parties they do business with,” the statement said.

Among the comments submitted to the DOT was a letter signed by members of Congress in support of the airlines’ position. The letter called it “highly unusual, if not unprecedented, that an agency use its regulatory authority to micromanage the business relationships of private companies in this way,” adding that, with the internet, “consumers have more information about airline fares, schedules and availability than ever before.”

Another group of House members signed a letter backing the online travel agencies’ position.

Keeping it in-house

But what airlines want to do is sell more tickets through their own websites, rather than through third parties — allowing them to have more control over the sale and sell bundles or a la carte options.

Delta vice president Rhonda Crawford said in a written statement that “most external channels that display Delta and other airline content skew toward sorting by the cheapest fare — even if that fare doesn’t deliver the best experience by way of schedule or amenities that are available and important to the customer.”

Delta in recent years has pulled its fares off a number of small online travel sites.

“Unfortunately, some online travel sites sell itineraries that are harmful to the consumer, add fees that Delta does not charge, or use false and deceptive advertising,” Delta spokeswoman Elizabeth Wolf said in a written statement.

Crawford said Delta is collaborating with distributors and online travel agencies, but said those third parties need to invest in more display capabilities to show more options for different tiers of fares. Ebenhoch said they already have.

“At the end of the day, we believe airlines want to eliminate third-party intermediaries and sell everything themselves,” Ebenhoch said. “And that will result in higher fares and less competition.”