The Department of Transportation fined Spirit Airlines $350,000 for pretending that passengers who were involuntarily denied boarding had volunteered to take later flights, and undercompensating those passengers. They called denied boardings “the “volunteer option”, and customers were forced to sign an “acknowledgement form” stating so.”

Spirit Airlines, with its low fares and focus on leisure travel, has customers who don’t know all of the legal nuances of travel. And airlines are obligated to tell passengers their rights. In a case investigated by DOT Spirit never told customers they were entitled to cash compensation for being involuntarily refused travel. They were told they had to take Spirit’s travel scrip instead.

The agency says the violations at the Miramar, Florida-based carrier took place between January 2017 and June 2018.

“We determined that in oversale situations, Spirit would first solicit volunteers to give up their seats in exchange for a future travel voucher, re-accommodation on Spirit’s next available flight or a flight on another airline, and hotel accommodations, if needed. If there were not enough volunteers, Spirit would then deny boarding to passengers involuntarily based on time of check-in,” the agency writes in its order.

These passengers were compensated and, if possible, re-accommodated on other flights. Spirit referred to this as the “volunteer option”, and customers were forced to sign an “acknowledgement form” stating so.

The U.S. government found ”a pattern of non-compliance with the compensation scheme” at Spirit. However not only was the fine just $350,000, the airline only has to pay $240,000 of it because they get credit for tickets purchased on other airlines for passengers who couldn’t be rebooked. Spirit for its part promises “appropriate changes” have been made.

Flying Spirit really is a different experience but its Big Front Seat remains one of the best values in travel if you can stand flying without inflight internet.