You are completely exaggerating and pointing out edge cases. Sure sometimes advertising can be harmful and there are laws against false advertising. But in general it is helpful and provides value. For instance I personally like it when I 'm shown a relevant advertisement which actually convinces me to purchase it. Just recently I saw some advertisement on Instagram related to some concert near where I live. It was actually relevant and I considered purchasing a ticket.
You can always exaggerate and cherry pick bad instances from anything. What you are doing is similar to this. There were a few Samsung phones that blew up and caused injury. You now characterise all phones as being harmful and dangerous to society.