Bartenders waer dark glasses because they don’t want to know what they’re pouring

IBIZA, SPAIN – JULY 08: Bartender Barrie Wilson attends the CIROC Party at Ushuaia on day 5 of the DIAGEO RESERVE WORLD CLASS Global Final on July 8, 2013 in Ibiza, Spain. (Photo by Ian Gavan/Getty Images for Diageo)