There are many research articles about perceptions of stuttering and stigma. Also, every person who stutters lives a different life. Where are you getting the phrase, “how many people we encounter seem indifferent?” Do people tell you that. They may think something but express indifference?? Depending on the person’s actions and conversation with them we would not know if it is sympathetic or empathetic. At this point you are asking how we view other people’s thoughts which are very dependent on what emotions WE are feeling and projecting onto someone else.