Loafanatomy

What do you call the crusty end of a loaf of bread?
I call it the heel. The dictionary backs me up.
Today, when I asked for the heel, the barista looked at me confused and asked,
"So you want the butt?"
"Beg pardon?"
She blushed.
"Do you want the butt?"
Never I have I heard it called that.
"No, I'll stick with the heel please."
Bon appetit.

What do you non-English speakers call it?