Princess Charlene poses after the arrival of the Riviera Water Bike Challenge in support of the Princess Charlene of Monaco Foundation, in Nice, France, June 4, 2017. (Photo by Eric Gaillard/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 reveller performs while attending the block party “Galo da Madrugada” during carnival festivities in Sao Paulo, Brazil on February 25, 2020. (Photo by Rahel Patrasso/Reuters)

People in Kathmandu joke that the face mask has now become part of the national dress – an indispensable accessory in an effort to protect themselves from the dust. Nepal has the worst air quality in the world, according to the Environmental Performance Index. (Photo by Pete Pattisson/The Guardian)

The Royal Conservatoire of Scotland has appeared in the world top ten for performing arts education in the QS World University Rankings 2024 published today, April 10, 2024. (Photo by The Times)

People watch the erupting craters and the lava fountains from the old lava fields around the eruption site on the Reykjanes Peninsula, in Iceland, Wednesday, August 28, 2024. (Photo by Marco di Marco/AP Photo)

Irish dancer Holly Venables on day three of the Cheltenham Racing Festival at Prestbury Park in Cheltenham, England on March 13, 2025. (Photo by David Fitzgerald/Sportsfile)

A mandarin duck swims through reflections of spring growth and blossom on a pond in Richmond Park in London, Britain on April 28, 2025. (Photo by Toby Melville/Reuters)