I once was buying an energy drink in the absurdly early morning on my way to work. In the pursuit of doing so, I stopped at a convenience store I had never visited before. I ended up the second customer in a line of two; the first was very visibly on … Something. Not in his right mind, is the point. He turned around and greeted me as the cashier scanned his items; I nodded and said hello, then made no effort to further the conversation.

After a surprisingly long pause during which I both suspected and hoped he had forgotten I was there, he refocused on me and said “HEY. Look at me when I’m talking to you.”

As I had done so, I was trying to figure out the least provocative way to respond. A moment later, the cashier said something - I don’t remember the exact words, but in essence it was a very calm “don’t bother customers in my store.” She didn’t yell or threaten, but the other customer immediately backed off. I was pretty impressed, to be honest.

Much as I was grateful for that cashier’s intervention, I never went back to that store.