I'm not sure most people understand this but it is much much much much harder to make a normal zoom than a telephoto zoom. You can make extremely good telephoto zooms day and night for cheap, as evidence by every manufacturers and all the third party telephoto zooms being great lenses.
Making a normal zoom, especially a fast normal zoom with IS is the greatest challenge their is. It is actually much harder to do than making a 200-400mm 1.4x TC lens.
I've spoken to Canon reps and Canon has gone to great lengths to try to make a pro image quality 24-70mm f/2.8 IS lens prototypes, even going as far as making a lens that has a 105mm filter thread.
Fast Normal zooms actually have much bigger elements than fast telephoto zooms do. The 70-200mm f/2.8 has 2 77mm elements and a 60mm element as it's largest elements. The 24-70mm f/2.8 Mk. I has three 77mm elements. The 24-70mm Mk. II has even bigger elements.
So yeah just because it looks bigger doesn't mean it's worth more, you're paying for more air, not glass. If anything a fast normal zoom should cost 2-3 times as much as a equal quality telephoto zoom. The only reason why telephoto zooms are the most expensive is because there is a market for them with sports and wildlife photographers.
Really? Hmmm. This does not go down at all with me. Naaa...