Section 5. Except as provided in section six, no bakery products shall be returned from any consumer or other purchaser to the dealer or baker, nor from any dealer to the baker, nor shall any dealer or baker directly or indirectly accept any returns from or make any exchange of bakery products with any person. All such products shall be kept moving to the consumer without unreasonable delay and without any practice whatsoever which may disseminate contagion or disease among or inflict fraud upon consumers, or disseminate ''rope'', so called, or other infection in bakeries, or cause waste in the food supply; provided, that this section, except in so far as may be necessary to prevent such waste, shall not apply to crackers or other bakery products which are packed at the place of production in cartons, cans, boxes or similar permanent containers, except paper or parchment wrappers used in wrapping loaves of bread, and which are so packed and sealed at such place as fully to insure the freshness and wholesomeness of such products and to protect them from contamination, adulteration and deterioration in the course of trade, and which remain in the original unbroken package as packed.