A model walks down the runway during the Safilo fashion show at the Mercedes-Benz Fashion Pavilion on January 30, 2012 in Stockholm, Sweden. (Photo by Ian Gavan/Getty Images)

A model walks the runway during the Craig Lawrence show at London Fashion Week Autumn/Winter 2012 at Somerset House on February 19, 2012 in London, England. (Photo by Stuart Wilson/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 winner of the Miss Tattoo Brazil 2014 contest, Bruna Barros, shows a tattoo that says 'My body, my rules' during Tattoo Week, the largest convention of art in the skin of Latin America, in Sao Paulo, Brazil, 14 July 2017. A tattooed woman beauty pageant, the new trends and techniques of the tattoo world, body piercing and the environment of the art of definitively painting the body, are all due to be addressed during the seventh edition of the “Tattoo Week Sao Paulo“. (Photo by Sebastiao Moreira/EPA)

In this Monday, June 29, 2020 a man wearing a face mask to protect against coronavirus, walks past a hair product billboard on the street in Soweto, Johannesburg, South Africa. Africa now has more than a half-million confirmed coronavirus cases as the continent-wide total is now over 508,000 after South Africa recorded another day of more than 10,000 confirmed cases as a new global hot spot. (Photo by Themba Hadebe/AP Photo/File)

A woman spends her time outdoors to observe the ancient festival of Sizdeh Bedar, an annual public picnic day on the 13th day of the Iranian new year, at the Tochal mountainous area northern Tehran, Iran, Sunday, April, 2, 2017. Sizdeh Bedar, which comes from the Farsi words for “thirteen” and “day out”, is a legacy from Iran's pre-Islamic past that hard-liners in the Islamic Republic never managed to erase from calendars. (Photo by Ebrahim Noroozi/AP Photo)

Miu Miu, a Chihuahua, poses at the pre-Westminster Fashion Show at Hotel Pennsylvania ahead of next week's Westminster Kennel Club Dog Show on February 10, 2012 in New York City. (Photo by Michael Nagle/Getty Images)

A woman walks with her child past a Soyuz rocket, installed as a monument at the Russian leased Baikonur cosmodrome, the world's first and largest operational space launch facility, in Baikonur, Kazakhstan, Saturday, November 12, 2016. The new Soyuz mission to the International Space Station (ISS) is scheduled for Friday, Nov. 18. (Photo by Dmitri Lovetsky/AP Photo)