Last year, Delta Air Lines announced it was testing out dynamic pricing on some flights using tools built by the tech company Fetcherr. And while the test was initially limited, executives from the company announced that 3% of flights now use AI pricing, and they hope to sell 20% of all tickets using a dynamic price by the end of the year.

Edward H. Bastian, the CEO of Delta, explained the strategy on an investors call last week, noting that it was “optimizing revenue through [its] partnership with Fetcherr,” an Israeli tech company founded in 2019, and “leveraging AI-enhanced pricing solutions.”

“So today, we’re about 3% of domestic. And that’s… our goal is to have about 20% by the end of the year, and that’s a goal,” Glen Hauenstein, the president of Delta, told investors on July 10. “I mean, we can report back on what the actual numbers are. But you have to train these models as you might, and you have to give it multiple opportunities to provide different results.”

Hauenstein said the company was in a “heavy testing phase” but that executives at the company “like what we see.”

“We like it a lot, and we’re continuing to roll it out, but we’re going to take our time and make sure that the rollout is successful as opposed to trying to rush it and risk that there are unwanted answers in there,” the president said.

What does that mean? If you ask critics like Sen. Ruben Gallego, a Democrat from Arizona, it means Delta isn’t being fair about the way it’s pricing seats.

“Delta’s CEO just got caught bragging about using AI to find your pain point—meaning they’ll squeeze you for every penny,” Gallego wrote Tuesday on X. “This isn’t fair pricing or competitive pricing. It’s predatory pricing. I won’t let them get away with this.”

But the company disputes the idea that there’s anything unfair about its use of AI to price fares, telling Fortune magazine, “Our fares are publicly filed and based solely on trip-related factors like advance purchase and cabin class, and we maintain strict safeguards to ensure compliance with federal law.”

Dynamic pricing is highly controversial and can lead to some intense backlash. When news broke back in early 2024 that Wendy’s was thinking about introducing surge pricing—making food items more expensive during certain times of the day—it backed off the plan almost immediately.

Will Delta face the same backlash? That seems likely, given the subsequent outrage you can see on social media. But that doesn’t mean Delta will be as responsive to the negative publicity. Delta makes a significant portion of its revenue from its partnership with American Express, meaning it’s less sensitive to people griping about the penny-pinching nightmare that is flying in the 21st century. Or, as the Atlantic put it in an article from 2023, airlines are just banks now. And banks don’t really care if you think they’re out to just make money without regard for their customers’ feelings.