Delta apologized, saying, “We apologize to this customer for her experience in the Boston baggage service office and Delta is in contact with her to better understand what transpired.”

This is not Delta’s first incident of this sort. Several years ago, Delta (DAL) had to apologize to an African-American doctor for first ignoring and then questioning her credentials when she offered to help another passenger in need.

The police-calling incident resembles one at a Starbucks, where two black men were arrested by the Philadelphia police while waiting for a friend. That incident led the company to institute chain-wide racial bias training. But airlines have less reason than coffee chains to change. While coffee drinkers can choose from thousands of coffee shops, the air travel market is a different beast.

Air travel and customer service

Airlines are one of those institutions that customers love to hate. They rank in the bottom third of sectors measured by the American Customer Satisfaction Index.

Part of the problem is that, long before online behavior tracking or social networks that dipped into your bank records, airlines had a pretty precise idea of what kind of customer you were, thanks to their mileage programs. They knew if you were a valuable business traveler, billing the champagne to the client, or a beleaguered bargain-hunting family carrying toddlers on your lap and packing a picnic.

Airlines treat passengers accordingly choosing which to involuntarily deny boarding on oversold flights based on issues such as fare class and frequent-flyer program status—i.e. how much they are worth. The most famous recent case of a passenger involuntarily denied travel was David Dao, the doctor who was dragged from his seat on a United flight after being subdued and bloodied by law enforcement officials.

And that rubs passengers the wrong way. Even corporate clients asked United (UAL) to do something about its service after the bloodied-passenger-removal incident.

“Flying isn’t an individual experience, it’s communal,” writes Sarah Steimer for the American Marketing Association, “While it’s important to make the most valuable passengers’ experiences the best possible, airlines need to use data to lift morale for all customers, rather than a select few.”

But airlines in the U.S. have few reasons to care too much about their customer’s experience. The U.S. government has allowed domestic airlines to form an oligopoly, with near-monopolies on certain routes, and protects them from foreign competition. Air travel regulations make it hard for disruptive startups to improve the industry from the bottom up.

“Compared to other industries, the financial return on passenger satisfaction is not much of an incentive,” said Claes Fornell, ACSI Chairman in a statement last year, “The exception is in the few airports where airlines actually compete with one another—or when they treat passengers spectacularly badly in public.”

The embarrassing thing is, despite all that protection, airlines aren’t always profitable.

Delta may learn the hard way that handling customers well is more important than handling baggage well.