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.

United States's Jessie Diggins celebrates winning the cross-country ski, women's Tour de Ski overall standings, in Val di Fiemme, Italy, Sunday, January 7, 2024. (Photo by Alessandro Trovati/AP Photo)

Honda Spanish rider Marc Marquez crashes with Aprilia Portuguese rider Miguel Oliveira during the MotoGP race of the Portuguese Grand Prix at the Algarve International Circuit in Portimao, on March 26, 2023. (Photo by Marcelo Del Pozo/Reuters)

In this Sunday, March 24, 2019, file photo, free skate pairs gold medalist Sui Wenjing and Han Cong of China perform during the gala exhibition for the ISU World Figure Skating Championships at Saitama Super Arena in Saitama, north of Tokyo. (Photo by Annice Lyn/AP Photo)

Jamaica's Tissanna Hickling competes in the women's long jump qualification during the World Athletics Championships at the National Athletics Centre in Budapest on August 19, 2023. (Photo by Kirill Kudryavtsev/AFP Photo)

Chase Jackson, of the United States, competes during the women's shot put qualification at the 2024 Summer Olympics, Thursday, August 8, 2024, in Saint-Denis, France. (Photo by Ashley Landis/AP Photo)

Pope Francis passes past a portrait of himself as he arrives to meet youths in Santo Tomas University in Manila, Philippines, Sunday, January 18, 2015. Francis is in the Philippines on Sunday, the final full day of a weeklong trip that also took him to Sri Lanka. (Photo by Alessandra Tarantino/AP Photo)

British model Kate Moss attends the Saint Laurent Womenswear Spring/Summer 2023 show as part of Paris Fashion Week on September 27, 2022 in Paris, France. (Photo by Pascal Le Segretain/Getty Images)