So the goal was to advertise advertising. A more scientific goal would be to see if there was an increase of in-store sales from internet advertising. Instead they were looking to design experiments that would show a positive effect, with the goal of giving advertisers a dashboard so they could run those experiments themselves.
I think you are misinterpreting what "do the experiments themselves" implies.
Certainly there is a JOIN with Google's or FB's data, but it can still happen entirely in a hosted sandbox with no data sharing necessary.
We've run Google's Local Campaigns, which are supposed to drive brick and mortar store visits, which they measure using GPS and "other signals". I checked with one of our most remote and least frequented stores, to see whether they could see any of the 100 daily visits that Google claimed to have generated, and they couldn't see a thing (avg daily visits were around 80 before during and after the campaign)
The goal was to demonstrate an impact of in-store sales from internet advertising. They did the first studies in about 2008-10, and have continued running these studies ever since.
They even built a tool so that advertisers can run these studies, and get a sense for the incremental impact of their ad.
Google have a similar (less full-featured) system.
Really, it's the rest of the ecosystem that has much of the fraud, and I think that a lot of people in the industry are aware of this.