I've built a relatively successful professional photography side hussle without "advertising" as in, I've never paid for an ad on any of the social platforms or google ads. Most of my business comes from word of mouth, or hits on my website.
But, is the SEO I do advertising? What about when I share my work to my socials, is that advertising? Post a reel of behind the scenes footage of me photographing a wedding so potential clients can see my process, is that advertising?
I do all of those things with the goal to drum up business, but they fall outside of the traditional meaning of the word. Likewise with product placement in films, influencer marketing, etc.
How do we even begin to draw the line at what is an advertisement and whats not?