Be careful what you wish for, Karen! If you're the type of person who sends a drink back at a drive thru, let's clarify a few things first, starting with what are you asking for. If it's a major modification to the menu or an innocent mistake, perhaps reconsider, especially if the line behind you lasts an eternity. This is not a Michelin star restaurant; it's a drive thru. Second of all, remember the old “you get what you get and you don't get upset” saying? That doesn't just apply to your kid,…