Tyson the Bulldog sits with reindeer antlers on Christmas Day at Central Park in Manhattan, New York City, U.S., December 25, 2016. (Photo by Andrew Kelly/Reuters)

A worker stack bricks on his head at a brick factory in Lalitpur January 12, 2015. (Photo by Navesh Chitrakar/Reuters)

Miss Talavera Bruce 2017, Mayana Rosa Alves, right, takes a cigarette break with two contestants before the start of the 13th annual Miss Talavera Bruce beauty pageant at the penitentiary the pageant is named for, in Rio de Janeiro, Brazil, Tuesday, December 4, 2018. Prison authorities say they organize the annual beauty contest to encourage self-esteem, fight idleness and promote integration among the female inmates. (Photo by Silvia Izquierdo/AP Photo)

Baka pygmies in their forest home preparing food in, Sangha Forest, Central African Republic, February 2016. Here, in their forest home, traditional life continues in the face of multiplying challenges ranging from poachers, to ill health. Deep in the rainforests of central Africa lives one of the world’s most mysterious tribes. (Photo by Susan Schulman/Barcroft Images)

Special Merit Award. Mallory Franklin (2019). The British slalom canoeist has competed internationally since 2009 and won nine medals in total at the ICF Canoe Slalom World Championships with four golds, four silvers and a bronze. She has also won eleven medals at the European Championships. (Photo by Richard Pelham/World Sports Photography Awards 2021)

In northwest Russia, in a small village called Alekhovshchina, Nadia Sablin's aunts spend the warmer months together in the family home and live as the family has always lived, chopping wood to heat the house and making their own clothes. Sablin's book of photographs, “Aunties: The Seven Summers of Alevtina and Ludmila”, is published by Duke University Press. Here: “Two-Handed Saw, 2014”. (Photo by Nadia Sablin)

People crowd onto 42nd Street as they take photos of the “Manhattanhenge” phenomenon in the Manhattan borough of New York July 11, 2014. Manhattanhenge, coined by astrophysicist Neil deGrasse Tyson, occurs twice a year, when the setting sun aligns itself with the east-west grid of streets in Manhattan. (Photo by Carlo Allegri/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.