Demonstrators hold masks depicting Colombian citizen Mile Virginia, who was murdered along with photojournalist Ruben Espinosa and three other women, during a protest in Mexico City, August 16, 2015. Espinosa, a prominent Mexican news photographer was among five people found dead in a middle-class neighborhood of the capital on July 31, 2015. Espinosa, who worked for the weekly magazine Proceso and the photo agency Cuartoscuro, had sought shelter in Mexico City earlier this summer saying he had been followed and threatened in the eastern state of Veracruz. (Photo by Tomas Bravo/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.

In a country where some 200 breweries produce well over 1,000 different beers, surely no one is considering brewing their own? Wrong. Here: Arnaud Laloy, member of the Belgian Homebrewers association, adds hop in the brewing process to create his own beer in the garage of his house in Neufchateau, Belgium, August 11, 2016. (Photo by Francois Lenoir/Reuters)

A Syrian man rides his bicycle past a man selling grains during a halt in fighting on February 29, 2016 in Douma, in the Eastern Ghouta region, east of the capital Damascus. A UN-backed ceasefire deal took hold across parts of Syria, bringing relative calm to areas where the Islamic State group and Al-Qaeda's local affiliate are not present. (Photo by Sameer Al-Doumy/AFP Photo)

A child, from Municipal school Parana, poses during the project “Fencing School” in Rio de Janeiro, Brazil, March 30, 2016. Children in Rio de Janeiro lift their sights and their swords to new idols, as a round of fencing workshops takes to public schools. The International Fencing Federation, together with the Brazilian and state federations, will reach 40 public schools in March and April. The aim is to whip up a following for the Olympic sport, little known in the soccer-mad nation, as Rio sets the stage for the Summer Games in August. (Photo by Sergio Moraes/Reuters)

Kiritimati is a far-flung outpost of the Republic of Kiribati. The world's largest coral atoll, Kiritimati has just one flight a week to either Fiji or Hawaii, four-and-a-half hours in either direction. Tarawa, the capital of Kiribati lies nearly 3,300 km (2,000 miles) to the west – about three weeks by boat. No lawyers are based on Kiritimati and the High Court only comes once or twice a year to clear a backlog of the most serious cases, bringing a public lawyer for defendants who can't afford their own. (Photo by Lincoln Feast/Reuters)

“The Red-eyed Treefrog (Agalychnis callidryas) is an arboreal hylid native to Neotropical rainforests in Central America. Red-eyed tree frogs, as their name states, have red eyes with vertically narrowed noses, a vibrant green body with yellow and blue vertically striped sides, and orange or yellow webbed feet and toes”. – Wikipedia. (Photo by Donald Quintana)

An isolated five-floor building stands in the middle of a new road on November 22, 2012 in Wenling, Zhejiang Province of China. Zhejiang Province of China. 67-year-old Luo Baogen and his 65-year-old wife from Xiazhangyang village still live in the half-demolished residential building, because they are dissatisfied with the relocation compensation. The road, which leads to the Wenling Railway Station, has not been put into use. (Photo by China Foto Press)