"We have Airheads." joke

Two blondes enter a drug store.
"
What kind of candy do you have here?"
asks the blonde.
"
Airheads."
replies the cashier.
"
What a jerk!"
yells the blonde as she starts slugging the cashier with her purse.
"
What are you doing?!?"
shouts the cashier.
"
Don't ever call us airheads!"
yells the blonde.
"
I was only telling you what kind of candy we have."