What FB is really doing is compiling a dossier of your statements, connections to other people, habits, preferences, and opinions.

FB is ostensibly saying 'we only use this information to connect you to the things you prefer and show you content you will like.' That's good guy FB trying to enrich your experience and who just happens (through innovation) to make money doing it.

Bad guy FB hopes to leverage its dossier to all of those who are interested, and it is unconcerned about the ultimate destiny of your data or in whose hands it end up in.

What we can say whether or not we subscribe to GG FB or BG FB theory is that the mere existence of a dossier is dangerous in and of itself. In terms of privacy, in fact, the argument isn't whether use of data is innocuous or not. It's instead why FB (and Google, etc) keep this information and the danger involved in its use as part of a business model.

The shorthand way of thinking about this is either a company is selling you a product, or you are the product being sold to some other company. For FB, Google, and for those for whom information is the product for sale, data about you is what is valuable. Value generated through social media interaction is a sideshow.

As users of products and services, we do not want heaps of data being stored about our every whim and action online. We don't want to be tracked everywhere we go, and especially for all of our independent activities to be cross-linked into a single universal dossier which is ready and available for some parties to utilise.

We should be able to go about our business, online and irl, without being surveilled, and we should have an expectation that companies exist to serve us (and protecting our data is part of their service) rather than those who want to find out about us.