In this August 24, 2019 photo, a tractor pulls a trailer that was converted into a swimming pool as it drives along the roads of El Infernal neighborhood in San Andres in the province of Pinar del Río, Cuba. The idea for the mobile tractor-pool was hatched by local parents, to make their kids happy and fight the harsh Caribbean heat. (Photo by Ramon Espinosa/AP Photo)

An art installation is on display at Gentle Monster's Multi-brand Space – Haus Nowhere Shanghai on March 20, 2024 in Shanghai, China. (Photo by Wang Gang/VCG via Getty Images)

Geese are walking under pear trees in full bloom in Shiliangliu village, West Coast New District, in Qingdao, China, on April 8, 2024. (Photo by Costfoto/NurPhoto/Rex Features/Shutterstock)

On October 31st, 2025, when the weather was in full autumn, citizens visiting the Taehwagang National Garden Chrysanthemum Garden in Nam-gu, Ulsan, are making memories among the chrysanthemums turning yellow. (Photo by Kim Dong-hwan)

Local villagers ride a local coal powered steam train on March 27, 2015 at a station in the town of Shixi , Sichuan Province, in Southern China. While China boasts the world's most extensive high-speed rail infrastructure with over 16,000 kilometers of track, the Shixi-Bagou railway is still a primary connection for local villagers between towns and is kept alive by tourist cars carrying passengers for ten times the price. The rail line came into service in the late 1950s and the train was initially used to transport coal from a now-shuttered mine before passenger carriages were added. (Photo by Kevin Frayer/Getty Images)

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 space shuttle Atlantis lifts off from launch pad 39A at the Kennedy Space Center in Cape Canaveral, Florida May 14, 2010. (Photo by Pierre Ducharme/Reuters)

Costumed revelers walk through a street prior to the carnival parade in the village of Vevcani, in the southwestern part of North Macedonia, on Wednesday, January 13, 2021. The coronavirus pandemic has disrupted the usual carnival celebrations which have been taken place for centuries in the tiny North Macedonian town of Vevcani. A few hundred locals gathered at the small town square to celebrate the carnival, but police dispersed the gathering after a brief scuffle with a small group. No arrests or injuries were reported. (Photo by Boris Grdanoski/AP Photo)