the girl from mississippi

A girl from Mississippi and a girl from California were seated side by side on an airplane.

The girl from Mississippi, being friendly and all said,
"So where y'all from?"

The California girl said, "From a place where they know better than to use a preposition at the end of a sentence."

The girl from Mississippi sat quietly for a few moments and then replied,
"So,where y'all from, bitch?"