How do you know that? Been flying planes or just saying that based off of other people saying it, much like the 'carrots help you see in the dark' lie

Anyone “should I tip this or this” “I’m not from here what should I...” “I have a question”

Its so disheartening to see how unintelligent this salty(and salty indeed) waitress truly is. Every question regarding tipping seems to be met with a pretentious response along the lines of “yeah you have to tip you fucking pleb otherwise don’t bother getting what you’re getting, oh it’s a coffee? A single coffee that…