It really bugs me how much they are charging these days for sweet tea and soda! That really raises the total on your bill.
We often just get water.
But I also have a trick that allows me to enjoy my iced tea well after I've left a restaurant. When we go out to eat, I always carry a plastic "to-go" cup I've saved from a previous visit to a place like Panera Bread or Atlanta Bread. We're talking BIG cup.
I sit it on our table and have the waiter fill it instead of their meager little plastic cups. And when I leave, it's always with a full cup of yummy iced tea for the road! (I also have a fancy for lemons-I carry them too) I know-nuts.

We all have our quirks...