It is hereby declared to be the legislative intent to encourage fair and honest competition; and to provide the retail merchants of this state with a freedom of choice concerning those books, pamphlets, magazines, periodicals, newspapers, picture magazines, comic books, story papers, and/or similar printed or written matters or materials which they might desire to offer for sale within their individual establishments; and to safeguard the public from exposure to printed or written materials or matters which appeal to the prurient interest, and concerning which the retail merchants of this state, or any one or more of them, might not desire to voluntarily offer for sale within their individual establishments.