When Is The Last Straw?

(I work at a well-known pretzel shop in an outlet mall near where I live. Customers are often rude to my coworkers or me, but I just grin and bear it, for the most part, to try and earn a living. Today is just another one of those days for me and the rest of my coworkers in the miserable life of retail/fast food work. A mother and her child walk into the store to order some pretzels and drinks. My manager and I are the only people running the store at the moment, so it’s not too hard to deal with only two customers. I’m rolling the pretzels while my manager is at the register dealing with said customers when this incident happens once they start to leave with their items. The child unwraps her straw wrapper for her drink and proceeds to chuck it OVER OUR REGISTER COUNTER and onto our kitchen floor. This exchange happens between my manager and the customer.)

Customer: “My daughter just threw her straw wrapper over the counter.”

Manager: “Okay…?”

(I thought to myself at that moment, “Well, no s***, Sherlock. And it looks like you didn’t teach yourself or your child to apologize when they do something wrong, either.” They left without apologizing or saying another word. After getting over our initial anger about it, my manager and I had a good laugh about it later and dreaded the next set of customers that we had to deal with. It’s sad because this was one of the lesser incidents that we’ve had to deal with all day, or all week, for that matter.)