Every single person I know well has a double standard for something. Such as “I don’t need to improve my driving but everyone else sure does” or a “do as I say not as I do” rule, etc. Though certainly some more than other. This leads me to believe all people do it in some way.
Is it simply human nature?
the element that is missed here is that people judge you via their interpretation of your behavior.
two different folks can see the same action in completely different ways, based on their psychology and their cultural expectations. what’s horrible rude to one person, might be a compliment to another.