Whereas in real life the product literally is 4-D, because not only can you see it you can pick it up and feel the product. CG imaging in "3-D" does not give the same experience and does not give the "true-to-life" quality as natural photography in the eyes of the consumer. In the same vein the "virtual store" concept also does not function for the explicit reason that when you have too much to focus on you're not likely to hone in on the singular product that you wish to buy and therefore you miss the trees for the forest. This is not merely an opinion due to the real fact that when major companies have ventured in this direction it has actually been a bust. This exhibits itself in the factor of loss of capital in the shape of shipment costs from returns of products that were bought as the result of a 3-D rendered image that didn't appear true to the actual product, not to mention the loss of capital in customer support costs, gateway transaction expenses, left over stock, and the dreaded bad customer reviews.
In short, 3-D CG rendering can not replace natural photography for the mere but important fact that it lacks the possibility for a composition which is pleasing to the eye, and therefore pleasing to your revenues.