A Palestinian girl is seen inside the giant jerry can filled with water as displaced Palestinians, sheltering in tents they have set up in schools and along roadsides, experience the increasing temperatures in Deir al-Balah, Gaza, on June 11, 2024. Especially children are the most affected by the extremely hot weather conditions, while the number of Palestinians migrating to Deir al-Balah is increasing day by day due to Israeli attacks on different parts of Gaza. (Photo by Hasan Jedi/Anadolu via Getty Images)

A girl plays a jump rope game at a school housing residents displaced by gang violence in Port-au-Prince, Haiti, Wednesday, May 15, 2024. (Photo by Ramon Espinosa/AP Photo)

A woman receives money at a food stand using the light of her mobile phone during a power outage affecting Caracas and other regions of the country, in Caracas, Venezuela on August 30, 2024. (Photo by Leonardo Fernandez Viloria/Reuters)

President of Spain's soccer federation, Luis Rubiales, right, hugs Spain's Aitana Bonmati on the podium following Spain's win in the final of Women's World Cup soccer against England at Stadium Australia in Sydney, Australia, Sunday, August 20, 2023. At left is Spain's Princess Infanta Sofia. (Photo by Alessandra Tarantino/AP Photo)

An aerial view of Syrian people flocked to the streets in the capital Damascus to celebrate US President Donald Trump's decision to lift sanctions in Damascus, Syria on May 13, 2025. (Photo by Amadeusz Mikolaj Swierk/Anadolu via Getty Images)

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)

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.