I've never seen one.
The reasons I've read are mostly emotional, other reasons because of technical issues that can be mitigated just changing the configurations, other reasons because they don't like Mark Zuckerberg.
Other reasons of why they don't like it are applied to G+ also, yet they use G+ w/o complains.
Now, if you can provide examples of valid reasons, then I'm all ears.
As I said, off in the weeds.
In any case, here's lots of counter examples for you: https://hn.algolia.com/#!/comment/forever/0/deleted%20facebo... (sorry, lots of emotional reasons in there too...it's hard to filter out a completely valid reason for stopping the use of something)
In other words, those people hate Facebook and they don't even know why.
Second, only 5 of the first 25 posts there even mention Google and most of those are also objecting to the same practices fro Google that they're objecting to from Facebook, so, as I said, you may be suffering from more than a little confirmation bias here.
So, you can't show me an example, I assume you are bluffing and neather you or anyone here has a valid reason to hate Facebook, at least not a reazoned one, just emotional.
There are many many posts on HN talking about why someone got rid of their facebook account, or begging for an alternative, or throwing them under the PRISM bus.
However, many of them give explicit reasoning (sometimes in great detail), so not part of some pro-google astroturfing campaign, and there are many posts extolling the virtues of facebook, if only for practical reasons, so if you've "never read a single positive thought", you're suffering from severe selection or confirmation bias.