A worker paints the face of a realistic pet plushie, at the Pampanga Teddy Bear Factory, in Angeles City, Pampanga province, Philippines on March 10, 2023. (Photo by Lisa Marie David/Reuters)

Mr. Grindell Matthews with his latest invention, the new photographic gun which is the latest development in sky signs. 1933. It can throw a beam of light 15 miles into the sky. (Photo by Fox Photos)

Television actress Catherine Fuller visits Trafalgar Square in London and feeds the famous pigeons. (Photo by Harry Kerr/BIPs/Getty Images). 26th June 1956

Hirunika Premachandra, a politician and a leader of Samagi Vanitha Balawegaya, a part of the main opposition party Samagi Jana Balawegaya, hugs a female police member during a protest near Sri Lanka's Prime Minister Ranil Wickremesinghe's private residence, amid the country's economic crisis, in Colombo, Sri Lanka on June 22, 2022. (Photo by Dinuka Liyanawatte/Reuters)

A Shi'ite Muslim woman bleeds after she was cut on the forehead with a razor during a religious procession to mark Ashura in Nabatieh, southern Lebanon on August 19, 2021. (Photo by Aziz Taher/Reuters)

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 mine detection rat is given banana as a reward after successfully identifying an inactive mine on July 2, 2015 in Siem Reap, Cambodia. The Cambodian Mine Action Center (CMAC) working with the Belgian NGO APOPO has recently begun testing the feasability of using large mine detection rats from Tanzania to help clear fields of mines and unexploded ordnance in one of the most bombed and mined countries in the world. (Photo by Taylor Weidman/Getty Images)

Rita Ora attends the World Premiere of JEREMY SCOTT: THE PEOPLE'S DESIGNER, presented by The Vladar Company and Quintessentially at the TCL Chinese Theatre on Tuesday, September 8, 2015, in Hollywood, Calif. (Photo by Matt Sayles/Invision for The Vladar Company/AP Images)