Baltimore Orioles center fielder Austin Hays leaps while taking the field prior to the first inning of a baseball game against the Cleveland Guardians, Tuesday, May 30, 2023, in Baltimore. (Photo by Julio Cortez/AP Photo)

Marcus Semien #2 of the Texas Rangers is doused with sports drink after the game against the Seattle Mariners at Globe Life Field on June 03, 2023 in Arlington, Texas. (Photo by Sam Hodde/Getty Images)

Karolina Kluskova of the Czech Republic formed one part of an artistic swimming duet at the European Games at Aquatics Centre in Oswiecim, Poland on June 22, 2023. (Photo by Sarah Meyssonnier/Reuters)

A BYU fan show his support during the first half of an NCAA college football game against Oklahoma, Saturday, November 18, 2023, in Provo, Utah. (Photo by Rick Bowmer/AP Photo)

Artist Lindsey Stirling performs at halftime of a NFL game between the Miami Dolphins and Green Bay Packers at Lambeau Field on November 28, 2024 in Green Bay, Wisconsin. (Photo by Patrick McDermott/Getty Images)

Tony the Tiger poses for a photo prior to the Tony the Tiger Sun Bowl Game on Tuesday, December 31, 2024 in El Paso, TX. (Photo by Jorge Salgado/AP Content Services for Kellogg's Frosted Flakes)

Everyone wants to get something for nothing - whether it's a lucky upgrade that means you can turn left when you get on a plane instead or heading off into the economy seats, or even getting a few extra features thrown in for free when you buy a new car.

As some of the sharpest businesses around, no-one understands this quite as well as casinos and that's why they all have a system that they call comps. It's short for "complimentary offers" and these are special treats specially designed to reward you for your loyalty to the casino in question. They're basically bonuses.

A man carries an injured woman in a site hit by what activists said were airstrikes carried out by the Russian air force in the rebel-controlled area of Maaret al-Numan town in Idlib province, Syria January 9, 2016. At least 70 people died in what activists said where four vacuum bombs dropped by the Russian air force in the town of Maaret al-Numan; other air strikes where also carried out in the towns of Saraqib, Khan Sheikhoun and Maar Dabseh, in Idlib. (Photo by Khalil Ashawi/Reuters)