Earlier quoted context omitted.
They get shown ads that might be more relevant to them than just an ad picked at random, which might make them more likely to buy the product displayed in the ad. I guess that could lead to some extra harm to their wallets, but otherwise I am with you on this one.
Why do people think ads only have to deal with buying stuff like your next take out meal or a book on Amazon? We have ads for politics, charities, public service, pubic image of famous people, etc. We have ads for basically everything. We've been doing this for over 100 years too! I'm pretty sure if ads only helped sell more hamburgers then politicians would spend their campaign money elsewhere. Surely someone in the…
Then in practice there are way more ads that sell you a worldview, adjust your desires in some small way that's small in one iteration but can transform your values over the years.
Also the problem isn't just the ads, but also the tools they use to keep you engaged with the ads and spend longer time on the platform. Their tactics follow the sparse rewards patterns that gambling also follows. They use lots of counter-intuitive patterns like intentionally throwing in irrelevant stuff, because it's how our brains are wired: we get hooked more if the interesting stuff only comes every once in a while, and otherwise it's boring. This gives the activity an overall unpredictable nature that makes our brains want to explore and understand and build a better model of this environment, to reduce this unpredictability. But if it's carefully designed and always in motion, shapeshifting in response to how the masses interact with it, it stays mysterious for our brain and we get hooked.
It's worrying how many otherwise smart people dismiss this saying "whatever, I don't buy luxury cars anyway, who cares if I saw some ads for them?" (and we could go into how the car companies can benefit from you seeing the ad even if you never buy the car yourself)
Marketing psychology and addiction psychology have developed a lot over the years and there is basically zero amount of this taught in normal schools. People just don't think in terms of these tactics. We are like some naive old trusting grandma in the eyes of the manipulators (who, by the way, aren't evil, they just want accomplishments, want to achieve metric targets, get good evaluations, get promoted, build their CV etc.).