Unfiltered Story #251807

I work as a cashier at the Kodiak Walmart. A few thousand people live on the island, so it’s pretty busy like most other Walmarts. Today was pretty normal until this happened:
(Teen walks up to the register with a basket full of potatoes)
(One conveyer belt trip for those potatoes later…)
Me: Hello there, kind sir. Cash or card?
Teen: Umbumumbumumbum, umbumumbumumbum. (I suspect he was saying “Cash, please.”
Me: What the hell? Can you speak English or is this some stupid joke?
Teen: Umbumumbum umbumumbum! (likely an insult)
Me: Sir, what on earth are you trying to say?
Teen: YOU’RE A SH*THEAD! HA HA!
(The teen then promptly rushes out the store without paying before getting caught by security in the parking lot. The biggest mystery is why he wanted those potatoes so much)