Ummm...
Scoop...
Totally disappointed in you...
"Advertising" is a part of Marketing...
So indeed the "Lighting" could be [and is] considered "Marketing"...
Here is the USA we call it "The Display"...
Advertising is really the part of the Marketing Campaign that brings the customer into the Store...
Double T
PS: I'll quote one of your famous sources:
Wikipedia
Marketing is a societal process that is needed to discern consumers' wants; focusing on a product/service to those wants, and to mould the consumers towards the products/services. Marketing is fundamental to any businesses growth. The marketing teams (Marketers) have the task to create the consumer awareness of the products/services through marketing techniques; if a business does not pay attention to their products/services and their consumers' demographics, the business would not be able to endure longevity.
Marketing tends to be seen as a creative industry, which includes advertising, distribution and selling. It is also concerned with anticipating the customers' future needs and wants, often through market research.
Advertising is a one-way communication whose purpose is to inform potential customers about products and services and how to obtain them. Every major medium is used to deliver these messages, including: television, radio, movies, magazines, newspapers, video games, the Internet (see Internet advertising), and billboards. Advertising is often placed by an advertising agency on behalf of a company.
Advertisements can also be seen on the seats of grocery carts, on the walls of an airport walkway, on the sides of buses, heard in telephone hold messages and in-store public address systems. Advertisements are usually placed anywhere an audience can easily and/or frequently access visuals and/or audio.