I would imagine the type of person who wants to avoid chit chat during a transaction is often the same type of person who would feel anxious about seeming rude if they outright said “I’m not in the mood for chit chat, please don’t talk to me.”

Being that exact type of person, this option seems like a godsend to me, and no more “black mirror-esque” than selecting “leave at the door” when ordering food delivery.