The Parrot World has evolved regarding what is a healthy diet.
Today, it seems to be settling around a Natural Diet. A diet that is based around healthy fresh foods including Veggies, and Fruits (commonly referred to as Chop) supported by a wide cross-section of natural seeds, grains, and nuts found in the region of the World that the specific Parrot came from. Pellets represents a percentage of the dry food component offered each day. The dry food component wants to be comprised of 'Human Grade' elements. i.e., it is grown, processed and packaged for Human Consumption, as its classification.
With Amazon's it no Sunflower or Sunflower like seed and no Peanuts. This resulting from Amazons need for a lower Protein based diet, since Amazons can easily develop Fatty Liver.