Working at a fast-food restaurant is one of the most challenging jobs. Dealing with rude customers, long hours, and lots of work, all for minimum wage, is difficult. If you are faced with an unruly customer making aggressive demands, always listen carefully to what they say because there may be an opportunity for the egg to be on their face.
As a teenager, I worked at a Mcdonald's on a highway rest stop over the summer. I was making the burgers in the back when a belligerent customer came up and ordered a cheeseburger with EXTRA ONIONS. He emphasized I WANT EXTRA ONIONS loudly and repeatedly and banged his fist on the counter because the last time he ordered EXTRA ONIONS, there weren't enough onions on it.
My manager also overheard the order because the customer was loud and rude to the cashier. I looked over at my manager, and he gave me a nod; he knew what I had in mind and that he would have my back.