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 dog wears fake eyes while riding a motorcycle in Samut Sakhon, Thailand June 23, 2016. (Photo by Jorge Silva/Reuters)

Street vendors hold campaign posters for presidential candidate Patrice Talon ahead of the second round of Benin's presidential election on Sunday in Cotonou, Benin, March 18, 2016. (Photo by Charles Placide Tossou/Reuters)

The Hindus of Nusa Penida, Bali, Indonesia, carry out their annual Ngaben cremation on April 4, 2022, when they place the bones of those who have died over the past year on to floating animal forms in a ceremony that is said to release the souls of the deceased. (Photo by Gede Sudika/Solent News/Rex Features/Shutterstock)

Mariam Ashraf, a teacher and “natural hair influencer”, speaks before a phone on a tripod and lights during a live-stream at her home in Egypt's capital Cairo on March 22, 2022. “Shaggy”, “messy”, “unprofessional”. Natural curls were once looked down upon in Egypt, where Western beauty standards favoured sleek, straight locks. Now, things are changing. (Photo by Khaled Desouki/AFP Photo)

Bride Yulia Tagil sits on the backseat of a bike as she arrives for her alternative wedding ceremony on a square in Tel Aviv July 25, 2010. The alternative wedding ceremony was intended to demonstrate against the current situation in Israel, where the only way for Jews to get married by law is through the Chief Rabbinate. (Photo by Nir Elias/Reuters)

A woman greets a street artist at the San Fermin festival in Pamplona, northern Spain July 8, 2016. (Photo by Eloy Alonso/Reuters)

Afghan children play on the remains of a Soviet-era armored personnel carrier on the outskirts of Jalalabad on February 15, 2016. Soviet troops withdrew from Afghanistan on February 15, 1989, after ten years of fighting against Mujahidin militiamen. (Photo by Noorullah Shirzada/AFP Photo)