The attorney general of Washington DC is suing Marriott for charging guests resort fees that are not disclosed at the time that reservations are made — an increasingly common industry practice that is not limited to Marriott alone.

According to ABC News, DC Attorney General Karl Racine contends that Marriott has illegally made millions of dollars from resort fees added to the price of stays.

The fees ostensibly cover services offered by the hotel other than lodging, such as access to pools and fitness centres and high-speed wifi. The also are sometimes called “amenity” or “destination” fees.

“This is a straight-forward price deception case,” according to the lawsuit.

“For at least the last decade, Marriott has used an unlawful trade practice called ‘drip pricing’ in advertising its hotel rooms whereby Marriott initially hides a portion of a hotel room’s daily rate from consumers.”

Travel Market Report reports that Marriott CEO Arne Sorenson said in an interview that the fees are “well disclosed” and that the company with fight the lawsuit.

“I don’t think the fees are going away,” he added.

“We do want to make sure that we’re continuing to deliver value for them, and you can only do that in some markets, and in some hotels. So I don’t anticipate we will end up with these fees in every hotel, and in markets where there is no extra features for guests.”