25. In the case of an act which contravenes any provision of section 18 or section 20, any person operating a commercial establishment who ordered, authorized or recommended such an act, or who consented thereto, is guilty of an offence and is liable, in the case of an act contravening a provision of section 18, to the fine provided for in section 24, and in the case of an act contravening a provision of section 20, to the fine provided for in section 23.