“What response on my part will bring this conversation to a speedy conclusion?”
Sheldon, The Big Bang Theory
The number of times that I have had this thought at work is frightening...
Unfortunately, I wouldn't bother saying this at work, but you can be sure that at some point when you are annoying a random store clerk, some of us are thinking this...or something a lot less polite but with the same intention, and we use shorter words that you can actually understand. (Oh, and the next time you are feeling superior to the person running your credit card through the cash register, keep in mind that he or she may actually have more formal education than you.)
Sorry, occasionally a workplace rant tends to surface despite my best intentions.