Because nobody expects...
I'm writing this post lounging like a lounge-lizard on a comfy three-seater sofa. When I'm driving from A to B, I'm sitting in a comfy chair. Basically, I have a cushy life. I go for a walk in the evenings and I go to many music events, but as I'm (a bit of) an information junkie, I spend many happy hours on-line, lounging on my sofa. My bad.
Thanks to technology and energy, many of us have labour-saving devices and horseless carriages. Therefore, many of us don't burn much energy from doing hard physical work and from having to walk everywhere.
Therefore, to maintain energy balance, many of us have to eat little food energy to maintain a reasonable weight and body composition. To get all of the vitamins*, minerals, fibre/fiber etc required for good health from little food energy requires the consumption of foods with high nutrient densities. You know where this is going, don't you?
*Except for Vitamin D, which requires sensible sun exposure between the
end of March and the end of September when your shadow is shorter than
If you enjoy irony, see What Did You Expect? Coca-Cola's Newest Anti-Obesity Ad Blames Chairs, Not Coke.
P.S. According to the BBC TV series "QI", the Spanish Inquisition gave thirty days notice of their arrival. Therefore, according to "QI", everybody expected the Spanish Inquisition!
P.P.S. As a cushy life results in muscles burning carbohydrate at a low rate, sedentary people are better-off eating less carbohydrates. See 10 Rules New Low-Carb Dieters Should Follow.