Why I hate drive-thru's

(Outside a Mexican food joint, in the drive-thru area)
...
I(shouting out): I want a bean chalupa and...
She: A bee? chalupa, okay, anything else...
I(not sure what she heard): No, a beannnn chalupa, not beefff...
She: Bean or Beef?
I: Beannnnnnnnn-uh.... not beeffffffffffff-uh... (louder) No beeffff... No beefffffffff... Only beannnnnnnsssss...
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