That's splitting hairs. Facebook and Google's main source of revenue is letting advertisers target users based on things Facebook and Google know about them.

I disagree. There's a big difference between selling customer data and selling selling ads to a demographic. Also, the excuse that companies like Microsoft and Apple get a free pass just because it's not their main source of revenue is a weak one. If you have an issue with the practice then don't be selective in your criticism.

Microsoft and Apple don't get any more of a free pass than Facebook and Google. Also, you could spend all day going into Google threads and asking why Facebook, Microsoft, and Apple are getting a free pass, or going into Apple threads and asking why Google, Facebook, Microsoft, and Robert Mugabe are getting a free pass, but it isn't a positive defense.

The issues occur when the demographic gets down to tiny sizes (or, it merged with other datasets to uniquely identify an individual).