I've talked to some wine professionals in US restaurants lately about what's tough in their work. A popular complaint is the occasional wine consumers, with big collections and so on, who like to show off at sommeliers' expense. In past decades they'd send back bottles as a matter of show, a couple of sommeliers mentioned. That fad has passed, but not the sentiment behind it. I imagine that no one here behaves like that, but it is a real syndrome.
Not all sommeliers know Poe's classic story, "The Cask of Amontillado," but it struck me that they would be an apt audience for it. In the story, the blustery wine connoisseurship of Fortunato (who is both powerful and abusive) is used to trap him into a nasty doom, by someone he has repeatedly wronged (Montresor). Below is an archival link, in case you know any hardworking sommeliers who might appreciate knowing about it.