A couple sit on the terrase of a cafe in Istanbul as seagulls fly over them on September 10, 2019. (Photo by Ozan Kose/AFP Photo)

A woman struggles to drink homemade alcohol poured from the mouth of an idol of “Swet Bhairab” during the annual Indra Jatra festival to worship Indra, Kumari and other deities and to mark the end of monsoon season in Kathmandu, Nepal on September 15, 2019. (Photo by Monika Deupala/Reuters)

Protestors from the Extinction Rebellion march on day six of protests stopping traffic in the city district of Melbourne, Australia on October 12, 2019. (Photo by ydney Low/ZUMA Wire/Rex Features/Shutterstock)

A woman smokes marijuana during the annual 4/20 marijuana rally on Parliament Hill in Ottawa, Ontario, Canada, April 20, 2017. (Photo by Chris Wattie/Reuters)

Snow falls as a woman walks her dog in the village of Podolye, 70 kilometers (43 miles) east of St. Petersburg, Russia, early Thursday, May 11, 2017. North winds brought snow to the east of the St. Petersburg region. (Photo by Dmitri Lovetsky/AP Photo)

A soldier walks on the bank of the river in central Pyongyang, North Korea on April 16, 2017. (Photo by Damir Sagolj/Reuters)

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.

“Grit and Glamour”, a retrospective of the late British photographer Elsbeth Juda, who fled Nazi occupation and came to England in 1933, is at the Jewish Museum, in London, until July 1, 2018. Here: Shelagh Wilson, Copacabana beach, Rio de Janeiro, 1951. (Photo by Elsbeth Juda Archive/Victoria and Albert Museum)