Mishnah Berachos 6:2 – The Shehacol Blessing
The shehacol is the “catch-all blessing,” made before partaking of food. Although, the blessing specifically applies to certain foods such as eggs, cheese, and milk that would not fall under other categories, like prei ha’adamah (fruit of the earth) and prei ha’etz (fruit of the tree). So, if there is an understanding that by default, the shehacol blessing (shehacol nihiyeh b’dvarot – who creates all things through His word) seemingly covers all foods, then why are there so many particulars?
By analogy, the question may be asked, that if blue is blue, why are there so many shades of blue, or any other color? The rich diversity of G-d’s creation, whether His beautiful artwork, a tapestry in the sky, or a canvas at sunset, is such because of its inclusion of so many diverse elements that blend in harmony with His creation, and abide in accordance with His will. To ignore the various shades of the color spectrum, or fail to differentiate between so many types of foods is to diminish the grandeur of G-d’s creation. These are only my thoughts and not a halachic answer.
Aside from any discussion on the proper blessing to make before partaking of food, consider the following: proper awe, reverence, and respect towards the Creator Who provided the food. There is a story of a peasant who would like to thank the baker for the bread he ate. Upon thanking the baker, the baker said not to thank him, thank the miller who ground the wheat. The miller said to thank the farmer who harvested the wheat. The farmer said thank the earth. The earth said to thank the rain that replenished the earth. The rain said to thank the clouds that made the rain. The clouds said to thank the sun, because, without sunshine, the wheat could not grow. The sun said to thank G-d who made all celestial beings. And so that is one way to understand why we praise G-d with blessings over food and show gratitude towards Him for the food on our table.
The Tree of Life 