Dave,   one comment in your post surprised me "the typical American diet is pretty close to the breakdown of  the zone".  To stay on a zone diet or 40/30/30 balanced type diet one has to eat very little breads, cakes, foods with sugar, soft drinks, etc. To stay with only 40% carbohydrates one has to be very selective on picking food with carbs and get carbs mostly from fruits and vegetables. That is why balance bars make such a convenient snack or breakfast when there is no time to prepare a balanced meal. In any event, I see very few Americans eating a diet anywhere near close to a 40/30/30 diet. But, I must admit that my comment is "anecdotal". 
  You also mentioned that doctor's recommend replacing junkfood cholesterol, and saturated fats with unsaturated fats. This is true, but somehow most Americans have actually gotten the impression that they are better off replacing these bad foods with low fat foods. Since most low fat prepared foods are high carb, people seem to end up eating a much higher carb % than 40%. 
  There are a few more items in your post that I view differently, but rather than get into that, I do want to say that I agree with you that the balance bar 40/30/30 breakdown can be duplicated. If  a bigger company comes out with a 40/30/30 product that tastes as well and gets more shelf space; I'll sell my stock quickly. My bet is that the bigger companies that could blow balance bar away will not commit the necessary resources to compete in this small niche for at least a few years. Of course, I've been wrong before so only time will tell. 
  Tom |