A woman reacts to having leaves thrown on her, while taking a photo, in Central Park as leaves begin to change colors on October 26, 2022 in New York City. Leaves around parts of Central Park have begun changing colors while much of Long Island and Upstate New York have already peaked. (Photo by Alexi Rosenfeld/Getty Images)

Flight crews of German airliner Lufthansa wear traditional Bavarian folk dress during a photocall to celebrate Oktoberfest at Munich Airport Franz-Joseph-Strauss International on September 15, 2022 in Erding, Germany. Lufthansa cabin crew will dress in the Bavarian traditional costume “Blaudruck Dirndl“ and “Lederhose” on several international flights during the Oktoberfest who kicks off this coming weekend and will run for three weeks. (Photo by Alexander Hassenstein/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.

Friends outside the convention center during opening day of the annual Comic-Con International in San Diego, California, United States July 21, 2016. (Photo by WENN/SIPA Press)

A man takes a photo as a puff of smoke comes from Mount Agung volcano, taken from the Rendang sub-district in Karangasem Regency on Indonesia's resort island of Bali on November 23, 2017. Thousands living in the shadow of the rumbling volcano on Indonesia's resort island of Bali fled on November 22 as fears grow that it could erupt for the first time in more than 50 years. (Photo by Sonny Tumbelaka/AFP Photo)

A young woman holds a weapon during a basic combat training for civilians, organized by the Special Forces Unit Azov, of Ukraine's National Guard, in Mariupol, Donetsk region, eastern Ukraine, Sunday, February 13, 2022. The United States is evacuating almost all of the staff from its embassy in Kyiv as Western intelligence officials warn that a Russian invasion of Ukraine is increasingly imminent. (Photo by Vadim Ghirda/AP Photo)

A utility worker clears snow by the Tomb of the Unknown Soldier in Alexander Garden during a snowfall in Moscow, Russia on January 28, 2021. (Photo by Vyacheslav Prokofyev/TASS)

Volunteers wearing personal protective equipment (PPE) carry the body of a victim of the Covid-19 coronavirus to a cemetery in Hlegu Township in Yangon on July 10, 2021. (Photo by Ye Aung Thu/AFP Photo)