That’s a strange view. Taken to an extreme, that would be a restaurant without an exterior sign, menus, or even a waiter explaining the food. You would literally know nothing about any product or service without marketing. Marketing is the act of “bringing a product to market.” Marketing isn’t advertising. A farmer displaying tomatoes on a table at a farmers market is marketing. A farmer buying billboard space with a photo of his tomatoes is advertising. There isn’t anything unethical about either practice.
Communicating about the availability of a product shouldn’t be considered unethical. Lying about that product on the other hand..