I understand what you're saying and not disagreeing. This
potential future analogizes well to poor people donating blood
and getting paid for medical testing. Statistically, it's
typically college students who need the cash that do these
things, but regular people also donate as well.
The analogy to prostitution is also a good one. But there are
two sides to prostitution. There is the negative, a poorly
managed business model where the worker gets crappy treatment
that is abusive, and then there is better business models, where
prostitutes are offered some protection.
I would say that Facebook's prostitution of our brainspace is
akin to the second model.
Example: This is a screenshot of my page as I saw it a few
minutes ago. What's that on the side? That's an ad. What's that
ad talking about?
Now I'm absorbing it consciously because I make myself aware of
ads - it's a hobby. But do most people? I don't think they do. I
think they don't pay DIRECT attention, but indirectly they
notice.
Next time they go to the store, they might consider buying that
product, or suddenly feel like bringing it up in a conversation.
It's so commonplace, we don't even see it. Is it evil? I don't
know, although a lot of money is put into industrial
psychologists - and they're WAY AHEAD in the science compared to
academics, because money is involved.