Every step in the supply chain adds risk.
The growing, cutting, processing, packaging, shipping, delivering, storage, displaying, and bagging of our food each creates a possibility of bad stuff being on it.
Think about the following for just a minute...
Besides the toxins and chemicals that we know are being sprayed on our food, like herbicides and pesticides, there are also animals (coyotes, deer, rabbits, cats, dogs, mice, rats, birds and bugs, etc.) that travel through fields and gardens carrying disease and urinating and defecating on our food.
That is just in the first part of our food's journey before we put it in our mouths.
The next part has our food cut and killed, thrown in open trucks, driven exposed for miles and warehoused all the while being sprayed with even more toxins. It's then processed, placed in plastic bags (or left exposed) and then, after weeks or months or even years, (like apples) it is ready for us to buy, eat and share with our friends and families.
Then our food is placed so that every person with an illness (flu, cold, runny nose, virus / bacteria) gets to touch, move, handle and sneeze on it and put it back for the next lucky shopper.