While this does not mean these foods are poor quality (read the ingredients list will say more here), this does speak to the fact you are likely dealing with a company that places costs over quality, which of course if sold at discounters such as Amazon, Dr. F & S, this is important.
Here is just one example using "New Life Spectrum Fish Foods" which although a good food, follows this generic base formula to meet prices points and then sell to mass marketers such as Amazon (one cannot make a top quality fish food and meet prices points)