Well, ads are commonly run on hopium. Sure, there's performance marketing where you pay for clicks, but at least last time I checked, paying for "impressions"

Well, ads are commonly run on hopium. Sure, there's performance marketing where you pay for clicks, but at least last time I checked, paying for "impressions" (how that's measured is up to Facebook et al) is far more common. And a lot of advertising I can think of is just "brand building" anyway, trying to get something in front of as many eyeballs as possible without a directly measurable result such as an immediate purchase. Sure, folks try to measure the impact of that, but it's hard, to say the least. The goal is that next time you need a new car, whenever that is, you're more likely to get an Audi cause there were a few in Avengers. Same principle outside product placement. Add to that the somewhat common practice of advertisers trying to steal each other's customers (it's pretty common to buy a competitor's name as keyword in search for example) and you've got a pretty well oiled self powering money making machine.