As a counterpart to this, you know you're in the North if you're handed unsweetened tea and a sugar packet when you ask for sweet tea.

A true Southerner would rather die than call that sweet tea. The whole point of sweet tea is hypersaturation -- dissolving more sugar in the tea than is possible at the given iced (cold) temperature, by doing the dissolution with hot tea. Some Southerners will claim that sweet tea isn't sweet enough if it isn't chunky.