In the work place, employers or managers will always call out the employees if they are doing something that is not liked or allowed. This allows employees to know what they should do and what they should not do. In public, people are prone to do distasteful things.
It comes to no surprise that a surprisingly large amount of the population have habits which the majority of people look down upon. Take for the example the legions of men who do not wash their hands after using the bathroom. Some do not even wash after taking a number two. When someone is behaving distastefully, they should be called out or they will forever keep doing it.