Baristas see the worst of their guests.
Before he started working at the café, Devon rarely talked to any hipster or goth people, now he’d talked to more than he could count of his fingers; being a barista was similar to being a bartender in some ways.
Source: [WP] You are a barista in a 24 hour coffee shop. Every night at 3:33am a demon appears for the Dark Lord’s latte. : WritingPrompts
We’ve been both. We’ve been a barista, we’ve been a bartender.
And being a barista is far, far worse than being a bartender.
As a bartender people will come up to you and try to behave their best, hoping they will be able to get faster service.
As a barista we will deal with whatever bartender wrought. And all baristas will try to make the experience palatable, to that person who just left the clutches of a bartender, hours ago.