Using the same reasoning as an experiment I did in elementary school many years ago, I shall attempt to explain why no one believes that "moderates" are moderate.
Put three bowls in a row; put very hot water in one; put very cold water in three; and tepid water in the middle bowl. Stick one of your hands in the hot bowl, stick your other hand in the cold water. Wait like this for several minutes. Then remove both hands from the bowls and put them in the middle bowl at the same time. Your right hand will experience a different temperature than your left hand. Dry your hands off, clean up the experiment then come back and finish reading.
Now assume that the Cold bowl is the extremest Liberals, and the hot bowl is the extremest Conservatives, with the tepid bowl being the "moderate". Now, you know that the middle bowl was a moderate temperature, but when you put your hands in it from their respective bowls your brain told you different. It told you that the hand that had been in the hot bowl had just been put in a bowl of cold water, and vice versa. Now imagine that you had left your hand in those bowls for years instead of minutes, assuming the water hadn't changed temperature, your hands would have felt a much larger difference.
Now do you understand why moderates are never moderate. It is because those viewing them are steeped in their own views.