As someone who was once employed in the coffee crafting arts, I can assure you: being a barista is an extremely difficult job. You have to deal with people at their crankiest every morning, endure days on end watching people pretend to work amid the glow of their laptop, and create delicate works of foam-based art that only, like, 98% of customers even bother to Instagram. A good barista might be a little snobby, but most are at least surface-level friendly.
But there is some coffee shop behavior that slowly chips away at the friendly heart underneath that gloriously asymmetrical haircut. Not outright abhorrent behavior, mind you, but little things that customers probably don’t realize are a nuisance. If you’re innocently going about your coffee-shop experience while engaging in the following behavior, you’re very likely urging a slowly simmering resentment into a hard boil.