Honest, naive question -- what makes human data worth so much? Is it speculation that it will be worth more in future that drives the feverish collection of it, or are there already concrete uses/buyers? It feels bigger and more urgent than to simply help brands sell their merchandise more effectively
Not really, it's having the ability to hack on human behavior, to make large amounts of people do things. Buying things is the obvious example, but there are other things (like giving X some attention, push a political cause, convince them of something ...)
And yes, you're of course right that things like this wouldn't convince X. That's not the point. The point is that 0.1% of facebook's audience is one massive group of people.