People watch fireworks light the sky as they attend a ceremony celebrating Noruz (Nowruz), the Persian New Year, at the Iran Mall shopping centre in Iran's capital Tehran, on March 20, 2022. (Photo by AFP Photo/Stringer)

A member of the Africa Roho Msalaba church throws a 2 month old baby into the air during the “Throwing babies into the air” ritual in Kibera Slum of Nairobi, Kenya on March 10, 2024. The babies of the members of the Africa Roho Msalaba church, who are not taken out of the house until they are 2 months old and are not allowed to be seen by strangers, are introduced to the community by being paraded through the streets with the 'throwing babies in the air' ritual. (Photo by Edwin Ndeke/Anadolu via Getty Images)

A child performs in the mutton bustin (sheep riding) at the rodeo performance of the 76th annual Cloverdale Rodeo and Country Fair in Surrey, British Columbia, Canada, on May 18, 2024. (Photo by Xinhua News Agency/Rex Features/Shutterstock)

A woman wearing leggings with the colours of the US flag walks along a street of Havana on February 18, 2015. President Barack Obama announced Thursday he will make a landmark visit to Cuba on March 21-22, pledging to address human rights as America pursues a historic thaw with its former Cold War foe. (Photo by Yamil Lage/AFP Photo)

A Palestinian beekeeper uses smoke to calm bees in the process of collecting honey at a farm in Rafah, in the southern Gaza Strip April 11, 2016. Rateb Samour sees 250 patients a day, whose complaints range from hair loss to cerebral palsy and cancer. He is not a doctor and has never worked in a hospital. Samour inherited the skill of bee-sting therapy from his father. From 2003 the agricultural engineer dedicated all his time to study and develop the alternative-medicine treatment of apitherapy, which uses bee-related products from honey, propolis – or bee glue used to build hives – to venom. (Photo by Suhaib Salem/Reuters)

Peerapong Butakul, a transgender person also known as “Bee”, waits backstage during a rehearsal ahead of the reopening of Tiffany's show after closing for almost three years due to the coronavirus disease (COVID-19) pandemic, in Pattaya, Thailand on August 31, 2022. (Photo by Athit Perawongmetha/Reuters)

Hollywood actress Malin Akerman helps King Digital Entertainment set the Guinness World Record for the World's Largest Hammock to celebrate the launch of its new game Paradise Bay on Wednesday, September 2, 2015, in Jersey City, N.J. (Photo by Charles Sykes/Invision for King World Entertainment/AP 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.