Blaze, 8, from Swindon, is covered from head to toe as he plays in the mud at Weston-super-Mare beach on August 4, 2019, as the tide recedes and the huge expanse of mud flats cover the beach where holidaymakers enjoy splashing around. (Photo by Ben Birchall/PA Images via Getty Images)

Ice covered leafs are pictured on a tree near Amstall in northern Austria, December 2, 2014. Freezing fog and rain covered parts of the region with ice, causing blocked roads due to fallen trees and closed schools for security reasons, local media report. (Photo by Heinz-Peter Bader/Reuters)

An Economic Freedom Fighters supporter shows a mock weapons during a demonstration in Pretoria on April 12, 2017 calling for South African President Jacob Zuma to resign. Tens of thousand demonstrators took part in the march to Union Buildings, the official seat of government, which was organised on Zuma's 75th birthday and came after nationwide rallies against the president last week. Zuma's recent sacking of respected finance minister Pravin Gordhan has fanned years of public anger over government corruption scandals, record unemployment and slowing economic growth. (Photo by Marco Longari/AFP Photo)

Spectators await the start of a cinema screening at a Kinostar De Lux Multiplex in the Moscow suburb of Khimki, December 7, 2014. Furniture retailer IKEA has converted one of the cinema halls, completely replacing standard seats with their furniture, according to local media. There are 17 double beds fitted in the hall, which was renamed to “It wakes love”. (Photo by Sergei Karpukhin/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.

Damselflies covered in dew rest on a wild flower by the Po River, northern Italy on August 15, 2016. (Photo by Alberto Ghizzi Panizza/Barcroft Images)