Here is a question to consider. If Facebook doesn't do this and all other companies do and use that data for optimization and measurement purposes, won't FB unilaterally lose out? The solution is either no one does it or everyone does it. There is no in between.
Why do you assume anyone has? Even if some do, why should the ones that don't have to answer to your assumptions?
When a thief gets caught, and they say "why don't you care about the other thieves?", nobody honors that with an answer.
Hey, you could even use something positive as example, e.g. that someone says something nice about X doesn't justify the assumption that they wouldn't also appreciate similar qualities in or achievements by Y. Criticism or praise, the principle is the same.
This is the classic race to the bottom, and it's not a valid defence in my excuse.