Republican Presidential Candidate Donald Trump kisses his wife Melania Trump as he introduces her during first day of the Republican National Convention in Cleveland, Monday, July 18, 2016. (Photo by Matt Rourke/AP Photo)

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.

American actress Sydney Sweeney arrives at the premiere of “Immaculate”, Friday, March 15, 2024, in Los Angeles. (Photo by Jordan Strauss/Invision/AP Photo)

Italian singer Benjamin Mascolo and American actress and model Bella Thorne attends the Milano Pride Event in Sempione Square on June 26, 2021 in Milan, Italy. (Photo by Mairo Cinquetti/NurPhoto/Rex Features/Shutterstock)

Finland's Heta Tuuri competes in the women's high jump qualification during the World Athletics Championships at the National Athletics Centre in Budapest on August 25, 2023. (Photo by Ben Stansall/AFP Photo)

A Kashmiri man cover his head with plastic bag as it snows in Srinagar, Indian controlled Kashmir, Thursday, November 7, 2019. The region received its first snow on Wednesday, bringing temperatures down drastically and affecting air and vehicular traffic. (Photo by Mukhtar Khan/AP Photo)

A man wears jacket in the colors of Iranian flag as he attends the annual rally commemorating Iran's 1979 Islamic Revolution, in Tehran, Iran, Saturday, February 11, 2023. (Photo by Vahid Salemi/AP Photo)

A youth poses while holding two fishes before his face in Iraq's southern port city of al-Faw, 90 kilometres south of Basra near the Shatt al-Arab and the Gulf, on May 18, 2020. In Iraq, a national lockdown to halt the COVID-19 coronavirus pandemic has found some unexpected fans: local businesses who no longer have to compete with Turkish, Iranian or Chinese imports. Those countries, as well as Saudi Arabia, Jordan and Kuwait, typically flood Iraqi markets with inexpensive products at prices local producers can't compete with. (Photo by Hussein Faleh/AFP Photo)