A girl applies henna patterns on her hands while waiting for customers, ahead of Eid al-Fitr celebrations, in Karachi, Pakistan on April 9, 2024. (Photo by Akhtar Soomro/Reuters)

Italian police remove “Bruciamo Tutto” (Let's burn everything) activists after they poured red paint on the Spanish steps (Piazza di Spagna), on June 26, 2024 in Rome, Italy. Today activists from “Bruciamo Tutto” (Let's burn everything) poured red paint on the Spanish steps (Piazza di Spagna) to protest against feminicides. (Photo by Antonio Masiello/Getty Images)

Archie, a Chinese Crested dog, sits with his tongue out before the start of the 20th Annual Ugliest Dog Competition at the Sonoma-Marin Fair June 20, 2008 in Petaluma, California. Owners of ugly dogs travel to Petaluma from all over the country to participate in the annual contest. (Photo by Justin Sullivan/Getty Images)

An Israeli woman scrambles through the mud and under barbed wire at the competition of the Legion Run in the Menara Cliffs area of Kiryat Shmona, in northern Israel, near the Lebanon border 14 October 2016. Hundreds of participants ran five kilometers cross country in steep terrain and then navigated various obstacle courses including steep inclines and mud holes. It is the first time this non-competitive but supportive sporting event is held in Israel. (Photo by Jim Hollander/EPA)

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.

Indian Air Force soldiers toss their rifles as they perform during the full-dress rehearsal for Indian Air Force Day at the Hindon air force station on the outskirts of New Delhi October 6, 2015. (Photo by Anindito Mukherjee/Reuters)

A commuter gestures to Boris Johnson as he rides across Vauxhall Bridge in London, England on November 19, 2015. The London mayor was opening a cycle superhighway. (Photo by John Stillwell/PA Wire)

Two cocks are trained for a fight in a village in Nakhon Sawan province, Thailand January 10, 2017. (Photo by Chaiwat Subprasom/Reuters)