In Zombieland the four main characters are Columbus, Tallahassee, Wichita and Little Rock. It's my understanding that the first two are named because that's where they're trying to get to.
The pair introduce themselves via where they're from
Where are you headed? Columbus.
Later Tallahassee refuses to give his name
What's your name?
Stop, no names. Keeps us from getting too familiar
However we're never given a reason behind the names of the two sisters. Throughout the whole film Little Rock and Wichita want to go to a theme park yet this doesn't seem to reflected in either of their names?