As most of you know, I am addicted to Diet Coke. Ergo, I spend a lot of time in McDonald’s drive-thrus. Frankly, it appalls me how people behave there. So, here is a review of public etiquette in a drive-thru. Kindly enjoy my sarcasm. Drive-thrus have become a staple in our society. They are great for short lunch breaks. You don’t have to…