Yes, this is a regional thing, I realize that. Which is to say, that if you drink iced tea outside of the South and don’t sweeten it – well, bless your heart, you just don’t get it.
This isn’t to say that unsweet tea is bad. People enjoy it around the world, and the Chinese have been drinking it for 2000 years. But iced tea is a relatively recent variation, as homes and restaurants have only had reliable sources of ice since the mid 20th century.
Some Southerners take the sweet thing a bit too far, however. The drink should be pleasantly sweet, but it’s not unusual to be served tea that’s almost sweet enough to cause tooth decay. Moderation is the key, as it tends to be in much of life.
If you ask for “tea” in the south, you’d better mean sweet iced tea. If that’s not what you want, be specific. Say, “I’d like some unsweet tea,” and don’t be too surprised if your server says, “Y’all ain’t from around here, are you?”