I think this actually paints a fairly rosey picture of what the average person eats, if you're looking at SAD standards. "Look at all those veggies and fruits! Not much meat, and look, sugar is so small compared to dairy and produce!"
Edit: They actually do separate corn, as 56 pounds of the 416 listed for veggies. About 13% of total vegetable intake is actually grain! I do wish they had broken down what part potatoes take of the remaining 360 pounds.
And milk is 181 pounds of the 600 pounds listed for non-cheese dairy...that's still 419 pounds of yogurt/sour cream/heavy cream/ice cream (24 pounds alone)...and I don't really know what else that would include!