The idea feels like sci-fi because you’re so used to it, imagining ads gone feels like asking to outlaw gravity. But humanity had been free of current forms of advertising for 99.9% of its existence. Word-of-mouth and community networks worked just fine. First-party websites and online communities would now improve on that.
The traditional argument pro-advertising—that it provides consumers with necessary information—hasn’t been valid for decades.
There is some awareness effect, too. If I like burgers and see a listing for a new burger place in my neighborhood, learning about a potential new place I’d like to include in my going-out rotation feels like a win. If I need a home repair and see a neighbor with a yard sign for a local contractor, that’s helpful in compiling a list of potential companies to check out.
What about word of mouth? If I want to find a good place to eat, I find asking a local “hey what’s the best restaurant around here?” to yield way better results than ads.