Fashionistas wait for the start of Johannesburg Fashion Week 2023 in Johannesburg, South Africa, Wednesday, November 8, 2023. (Photo by Jerome Delay/AP Photo)

A swimmer goes for a dip in freezing temperatures at the Serpentine Lake in Hyde Park, central London on December 1, 2023, as temperatures in the capital dip below zero for another night. The Met Office has issued a yellow weather warning for parts of the UK with freezing temperatures and snow expected in large areas. (Photo by Ben Cawthra/London News Pictures)

People in colorful costumes perform acrobatics for drivers waiting at red lights in Nairobi, Kenya on February 20, 2024. (Photo by Gerald Anderson/Anadolu via Getty Images)

In this handout image provided by Red Bull, Maria Paula Quintero of Colombia dives from the 21.5 metre platform during the second competition day of the third stop of the Red Bull Cliff Diving World Series on June 29, 2024 at Polignano a Mare, Italy. (Photo by Dean Treml/Red Bull via Getty Images)

Actors Ryan Reynolds, Blake Lively, fashion model Gigi Hadid and Hugh Jackman attend the premiere of “Deadpool and Wolverine” in New York City, New York, U.S., July 22, 2024. (Photo by Caitlin Ochs/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.

Mongolian herder, Khurelsukh, throws the carcass of a goat onto a heap as he struggles to deal with losing a quarter of his herd, on March 8, 2010 in Bayantsogt, Tuv province, Mongolia. (Photo by Paula Bronstein /Getty Images)

Artist Kong Ning wears a wedding dress made from respirators to highlight concerns about air quality and pollution in Beijing, China on December 1, 2015. (Photo by Luo Xiaoguang/Xinhua Press/Corbis)