Why? Any government that supports ads needs to be eliminated, in my opinion.

Ads work, so does PR, so do bot farms, underhanded influence campaigns and other dirty tricks. There are limits: Elon can't save more than one or two congressional Republicans for the $300 million he's spending on it. But in general, our government can in fact be bought, especially in cases where the vote might be close. It's not an exaggeration that we have an oligarchy problem.

I agree with most of your statements, e. g. mass surveillance and what not.

But I think you make one basic mistake with the "ever purchased something solely because of an ad". Because I believe you may not fully understand human psychology.

Not all ads work as a "buy this now". Some use annoying noises or visual effects to hook a message into the brain. Others just do an ad to promote the brand; that's why they use simple and stupid slogans "that stick".

There are many more reasons here, too many to explain in detail. The bottom line is that ads are not solely confineable towards a "it must get people to buy the product". Yes, that is the base line, but the evil ad company works with various tricks, including targeting children, e. g. the "nagging factor". There are excellent books of how this mafia works. Hopefully we'll eventually manage to abolish ads completely. Naturally with Google's adChromium, this will be a fight mankind has to win in the long run.