I was hired to work a retail position once and the manager set me up to train with what he called his top cashier.  Thou he did advise me that her cup of water, wasn’t in fact water, but gin.  Apparently she sipped it all day long and the buzz helped her function and management didn’t care.  About six months later she disappeared into rehab and was never seen again.  Perhaps she moved to a Cabin In The Woods?