I work in a restaurant in a hotel on sundays, and weeknights I work at a bar.
The hotel brings in a lot of impatient snobs who expect things to be done instantly - and naturally don't treat you like a human being. But in all fareness I have more issues with my fellow waitresses (who do nothing but chat and smoke instead of working) and my 60-year old manager.
The bar however isn't that bad. However, it's noisy - and some can't appreciate that hearing can be a problem! So they request their drinks quietly - Speak up you arseholes!
Though the customer I hate the most is the one that throws change at you! Careful or some particular bartender might throw a drink at you
Jam it back in, in the dark.