It is unlawful for any person who is not the holder of a license to practice optometry, to engage in the practice of optometry, directly or indirectly, by employing or hiring upon a salary, commission, or other profit-sharing arrangement a licensed optometrist except as permitted by the rules and regulations of the board. The provisions of this section do not apply to a physician licensed under chapter 43-17, a hospital, or a clinic operated by licensed optometrists or by licensed physicians.