An association shall be deemed not to be a conspiracy, nor a combination in restraint of trade nor an illegal monopoly; nor an attempt to lessen competition or to fix prices arbitrarily or to create a combination or pool in violation of any law of the state; and the marketing contracts and agreements between the association and its members and any agreements authorized in this chapter shall be considered not to be illegal nor in restraint of trade nor contrary to the provisions of any statute enacted against pooling or combinations.