The number one rule in sports should be "cheaters never prosper." Hockey fans have filed a "beer lawsuit" against CenturyLink Arena, home of the Idaho Steelheads hockey team, claiming that venue is defrauding its customers.

According to the Associated Press, four Steelheads fans filed a lawsuit in Boise's 4th District Court against the arena. They stated that the arena sells large beers for $7, even though they contain the same amount of liquid as the $4 small beer cup.

Brady Peck, Michele Bonds, and William and Brittany Graham are seeking $10,000 in damages for the money they claim to have lost over the past five years by purchasing the "larger" size for $7 instead of the $4 "small." Peck claims that he has purchased beer at the arena at least 30 times. The suit accuses the arena of using "unconscionable methods."

"While different shapes, both cup sizes hold substantially the same amount of liquid and are not large versus small in actual capacity," attorney Wyatt Johnson wrote in the lawsuit, according to the AP. "Defendants knowingly sold each of their beers in a similar manner at each event held at the arena where beer was sold for at least the last five years."

The lawsuit filing came after a YouTube video posted by fan, Gwen Gibbs, showed her testing the beer amounts right at the concession stands at the arena. Gibbs, who attends games with her boyfriend Heath Forsey, told The Idaho Statesman that she became upset when she realized that the large and smalls cups held exactly the same amount of liquid.

"It's amazing what can be done with one little video and the power of social media," said Gibbs, who is not involved in the lawsuit, to the newspaper.

Idaho Steelheads and CenturyLink Arena president Eric Trapp acknowledged the mistake and said he never intended to mislead customers. Trapp wrote on the team's Facebook page that the company had ordered 16-ounce and 20-ounce cups and never intended to mislead customers.

"It was recently brought to our attention that the amount of beer that fits in our large (20-oz) cups also fits in our regular (16-oz) cups," Trapp said. "The differentiation in the size of the two cups is too small. To correct that problem, we're purchasing new cups for the large beers that will hold 24 ounces, instead of 20, for the remainder of this season to provide better value to our fans. As we do every offseason, we'll evaluate our entire concessions menu for next season over the summer."

CenturyLink Arena hosts various concerts and events, and also serves as the home of NBA Developmental League team the Idaho Stampede.