An eight-year-old St Bernard with the longest canine tongue in the world, measuring 18.58cm (7.31in) in length, as recorded by the Guinness World Records: Amazing Animals, in South Dakota, USA. (Photo by Kevin Scott Ramos/GWR/PA Wire)

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.

The first autonomous and electric shuttle of PostAuto Schweiz in the old village of Sion, Switzerland, June 2016. (Photo by Ruben Sprich/Reuters)

Horses are spooked as the Woolsey Fire moves through the property on Cornell Road near Paramount Ranch on November 9, 2018 inAgoura Hills, California. About 75,000 homes have been evacuated in Los Angeles and Ventura counties due to two fires in the region. (Photo by Matthew Simmons/Getty Images)

Mariam Emad from Parkour Egypt “PKE” practices her parkour skills around buildings on the outskirts of Cairo, Egypt on July 20, 2018. A group of Egyptian women gather at an abandoned park in a Cairo suburb once a week, climbing walls and jumping around in the strenuous physical discipline known as Parkour, while also challenging the country's conservative social norms. (Photo by Amr Abdallah Dalsh/Reuters)

A woman plays on a swing on the beach in Santa Monica, Calif., Wednesday, June 22, 2022. (Photo by Jae C. Hong/AP Photo)

A photo taken on October 20, 2024, shows various patterns left on the beach after the ebb tide at the Yanghe Estuary wetland in Jiaozhou Bay in Qingdao, Shandong province, China. (Photo by Costfoto/NurPhoto/Rex Features/Shutterstock)

An aerial image shows hot air balloons, mostly made from recycled paper and tied with ropes, floating in the air during the annual hot air balloon festival, held since 1950 to celebrate Eid al-Fitr, the Islamic holiday marking the end of Ramadan, in Wonosobo, Central Java, on April 2, 2025. (Photo by Devi Rahman/AFP Photo)