In this Sunday, March 2, 2014 photo, animal barber Mohamed Mahmoud shaves a customer's initials onto the rump of a donkey in Cairo, Egypt. Clients typically request for regular trims to keep animals cool in the summer, initials in English letters, and patterns – but sometimes they give Mahmoud full creative license. (Photo by Maya Alleruzzo/AP Photo)

Humanoid robot bartender “Carl” interacts with guests at the Robots Bar and Lounge in the eastern German town of Ilmenau, July 26, 2013. “Carl”, developed and built by mechatronics engineer Ben Schaefer who runs a company for humanoid robots, prepares spirits for the mixing of cocktails and is able to interact with customers in small conversations. (Photo by Fabrizio Bensch/Reuters)

Vendors selling marigold garlands, which are used to decorate temples and homes during the Hindu festival of Durga Puja, drink tea as they wait for customers at a wholesale flower market in Kolkata, India October 6, 2016. (Photo by Rupak De Chowdhuri/Reuters)

People in hard hats in a rage room in Moscow, Russia on January 27, 2016. The Debosh stress relief service gives its customers an opportunity to smash the rage room up with sledgehammers and bats to relieve stress and tension. (Photo by Artyom Geodakyan/TASS/Barcroft Media)

This picture taken on March 1, 2016 shows a man running a mobile pig mating service and waiting outside a customer's home with his male pig in a cage pulled behind his motorcycle in the northern province of Bac Ninh. (Photo by Hoang Dinh Nam/AFP Photo)

A sales woman of a fish shop shows king crabs to a customer and negotiates the price in Noryangjin Fish Market is seen on August 1, 2015 in Seoul, South Korea. Noryangjin Fish Market was established in 1927 as Gyeongseong Susan in Jung-gu near Seoul Station and moved to its current location in 1971. (Photo by Shin Woong-jae/The Washington Post)

A woman rides a custom bike during "Bike Kill 12" in the Brooklyn borough of New York City, October 31, 2015. "Bike Kill" is an annual gathering of builders and riders of home-made bicycles that culminates in a tall bike jousting competition. (Photo by Stephanie Keith/Reuters)

Two working girls entertaining themselves in the absence of customers at the Moonlite Bunny Ranch, a legal brothel owned by Dennis Hof, in Lyon County, one of the fews counties in the USA which permits legalized prostitution. (Photo by Stephan Gladieu/Getty Images)