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.

A masked woman poses for a picture during a march demanding justice for the victims of gender violence and femicides in Mexico City, Mexico on August 16, 2020. (Photo by Raquel Cunha/Reuters)

Joshua Patino stands on a ladder to put finishing touches on a giant dinosaur exhibit at PAX East in the Boston Convention and Expo Center, Thursday, April 21, 2016, in Boston. PAX East, an annual celebration of gaming culture, is expected to draw tens of thousands of visitors Friday through Sunday. It's a place where serious gamers can preview unreleased video games and devices, compete in tournaments, hear live music and meet others for whom gaming is a way of life. (Photo by Elise Amendola/AP Photo)

People arriving for Ladies day at the EBOR Festival at York Racecourse in Yorkshire, England on August 18 2022. (Photo by Matthew Lofthouse/South West News Service)

An Olive Ridley sea turtle hatchling releases into the sea at Lhoknga beach, Indonesia's Aceh province on January 16, 2024. (Photo by Chaideer Mahyuddin/AFP Photo)

A helicopter drops fire retardent to protect a property in Balmoral, 150 kilometres southwest of Sydney on December 19, 2019. A state of emergency was declared in Australia's most populated region on December 19, as a record heat wave fanned unprecedented bushfires. (Photo by Peter Parks/AFP Photo)

A golden huddle by Minqiang Lu, China. Two females and a male golden snub-nosed monkey huddle together to keep warm in the extreme cold. Threatened by forest loss and fragmentation, this endangered species is confined to central China. Restricted to living high up in the temperate forests, these monkeys – here in the Qinling mountains in Shaanxi province – feed mostly in the trees, on leaves, bark, buds and lichen. In heavy wind and snow, Minqiang walked up the mountain carrying his equipment. He stayed for half an hour in temperatures of –10C opposite the tree where the group was huddled before achieving this eye-level composition. (Photo by Minqiang Lu/Wildlife Photographer of the Year)

Brazilian tattoo artist Michel Praddo, also known as Diabao or Human Satan, and his wife Carol Praddo, known as Mulher Demonia or Demon Woman, take a picture with a fan at the beach shore in Praia Grande, Brazil on August 18, 2021. (Photo by Carla Carniel/Reuters)