Londoners sleep on the platform and on the train tracks at Aldwych Underground station,London, during heavy all night Nazi bombing raids, October 8, 1940. (Photo by AP Photo)

An Egyptian street vendor carries plastic dishes on a street decorated for the holy month of Ramadan in old Cairo, Egypt June 1, 2016. (Photo by Amr Abdallah Dalsh/Reuters)

American film director Mike Todd and his actress wife Elizabeth Taylor get into a spat after missing their flight from London to Nice on June 22, 1957. (Photo by AP Photo)

Desmond Boylan, a photographer who covered war and conflict across the world before dedicating his life to documenting the daily joys and tribulations of life in Cuba for Reuters and The Associated Press, died suddenly while on assignment on Saturday, December 29, 2018 afternoon in Havana. Here: Cuban President takes a glass during a ceremony in the Oporto Bourse where he and other Ibero-American leaders were made members of the Port Wine Brotherhood in Portugal, October 1998. (Photo by Desmond Boylan/Reuters)

American actress Kate Hudson gives a shoutout to Italian luxury fashion house Maison Valentino in the second decade of July 2022. (Photo by katehudson/Instzgram)

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.

In this photo taken Tuesday, June 23, 2015, a Ukrainian serviceman from the Kiev-2 volunteer battalion fires an weapon at a frontline in the village of Krymske, east Ukraine. Few places along the front line in east Ukraine see regular fighting as bitter as the village of Krymske. For now, Krymske is in the hands of Ukrainian government forces and the volunteer battalions that fight alongside them. (Photo by Evgeniy Maloletka/AP Photo)

Two styles of cleaned bird's nest, Yan Zhan (L) and Su Zhan (R) await repacking at a processing plant in Kuala Lumpur, February 17, 2015. Prized in China for is alleged health benefits for hundreds of years, nests made from swiftlets' saliva are being mixed into coffee and cereal as the Southeast Asian producers of the delicacy seek to broaden its appeal, and their profit margins. The nests are among the world's most expensive foods, selling for up to $2,500 a kg and the swiftlets that weave them are indigenous to Indonesia, Malaysia, Thailand and Vietnam. (Photo by Olivia Harris/Reuters)