Not only is Google the seller, buyer, and auction house in the add market, but the whole behavioral ad market has destroyed display advertising for real websites like newspapers. You can apparently just advertise to newspaper readers on other, cheaper sites, instead of on the original paper.
From Corey Doctorow in 2020:
"Say you visit the Washington Post. Dozens of brokers bid on the chance to advertise to you. All but one of them loses the auction. But every one of those losers gets to add a tag to its dossier on you: “Washington Post reader.”
Advertising on the Washington Post is expensive. “Washington Post reader” is a valuable category unto itself: a lot of blue-chip firms will draw up marketing plans that say, “Make sure we tell Washington Post readers about this product!”
Here’s the thing: the companies want to advertise to Washington Post readers, but they don’t care about advertising in the Washington Post. And now there are dozens of auction “losers” who can sell the right to advertise to you, as a Post reader, when you visit cheaper sites.
When you click through one of those dreadful “Here’s 22 reasons to put a rubber band on your hotel room’s door handle” websites, every one of those 22 pages can be sold to advertisers who want to reach Post readers, at a fraction of what the Post charges."