When we’re frustrated with a store policy, or just plain having a bad day, it’s easy to take it out on an employee who is trying to do their job. It’s human nature, but it’s a really sucky move, and one that even the nicest people have been guilty of.
Word of advice: try to remember that, in most cases, it’s not the fault of the person in front of you. Moreover, these folks typically have it in their power to turn your bad experience to a slightly better one. So try to catch more flies with honey the next time you feel the urge to be a dickhead to someone in the service industry.