Not that the FAA necessarily cares, but there is a real distinction to be made. The distinction is that people are paying for a product. They are not paying you to transport their property like they would FedEx. They are not coming to you and saying, "I'll pay you to ship my product to someone." They are saying, "I will buy your product." That the farmer is flying his own product isn't in the air carrier business. In fact, he is probably losing money on the deal. To the extent one can even say that they are transporting property for hire, it falls within the ordinary meaning of "incidental." The FAA has changed the meaning of "incidental" in it's interpretations. "Foreseeable and normal" is not the opposite of "incidental." "Goodwill" is a term of art that is defined in the law, but the FAA uses it as a catch all to allow them to find compensation when they can't prove actual compensation, but really want to shut someone down.