Nothing illegal about it. In the jurisdiction where I live, anyone can offer for sale anything he has to sell, for any amount he wishes to sell it for, in excess of MSRP. Or less than MSRP if he desires. The retail customer has two choices. Buy, or don’t buy.
On the other hand, I was in the retail jewellery business 45 years ago, working for a jewellery chain. The managing director of a (name not specified) major watch manufacturer walked into the store during our annual sale. We had his line of watches ticketed at 25% off. I was told to remove the sale price tags. I did. They went back on the following day. Without getting into the whole sordid story about what followed, about 5 years later, I was subpoenaed to appear as a material witness at a trial in Toronto. It was a five day trial! I was asked if I had ever been told to remove sale price tickets from the product line in question. My answer was in the affirmative. That court case cost that company $28,000.00. Probably $75,000.00 today. The department of consumer and corporate affairs had charged that brand with price fixing. The only recourse a company has is to refuse to sell their product to an offending retailer.
This particular managing director was new in Canada, from Switzerland. Do I understand that Switzerland has legislation that makes it illegal to offer a product for sale for LESS than MSRP. Apparently, 45 years ago, that was the law there.