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.