Model Olivia Culpo (L) and host Nick Jonas, after getting slimed, backstage during Nickelodeon's 28th Annual Kids' Choice Awards held at The Forum on March 28, 2015 in Inglewood, California. (Photo by Lester Cohen/KCA2015/WireImage)

A Tufted Capuchin sits in a hanging food tray on a tree in it's enclosure at Sydney Zoo on February 24, 2020 in Sydney, Australia. Sydney Zoo, located at Bungarribee Park in Western Sydney, is the first new zoo to be built in Sydney in more than 100 years. The Zoo opened to the public on 7 December 2019. (Photo by Mark Kolbe/Getty Images)

Romanian singing duo Gabriella and Monica Irimia, The Cheeky Girls prforms in Falkirk, Scotland on May 4, 2003. (Photo by Michael Schofield/News Group Newspapers Ltd)

Olympic medal winning twins Jessica (left) and Jennifer Gadirova celebrate their GCSE results at Aylesbury Vale Academy in Buckinghamshire, United Kingdom onThursday, August 12, 2021. (Photo by Steve Parsons/PA Images via Getty Images)

Max Verstappen of Netherlands and Red Bull Racing prepares to drive in the garage during practice for the F1 Grand Prix of Spain at Circuit de Barcelona-Catalunya on August 14, 2020 in Barcelona, Spain. (Photo by Mark Thompson/Getty Images)

Mug shot of William Stanley Moore, 1 May 1925, Central Police Station, Sydney. This picture appears in the Photo Supplement to the NSW Police Gazette, 28 July, 1926 captioned: “Opium dealer. Operates with large quantities of faked opium and cocaine. A wharf labourer; associates with water front thieves and drug traders”. (Photo by NSW Police Forensic Photography Archive, Justice & Police Museum, Histiric Houses Trust of NSW)

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 Pakistani scavenger girl writes on a notebook she collected from a garbage, while another girl sits next to her in Lahore, Pakistan, Wednesday, April 1, 2015. Thousands of children pick recyclable items from waste dumping points to earn living for their poor families. (Photo by K. M. Chaudary/AP Photo)