Facebook is a great piece of software. Facebook is also breaking any privacy rules they can get away with breaking. Which way should we judge them? Sorry, for some people it's both.
Compare something like flow [1], reason [2], or prepack[3] as it's tools which serves you rather than the company behind it with access to the source which is the same as the case for weboob if you want to compare against facebook. I don't see an issue with using them though as they don't collect data on you.
[1]: https://github.com/facebook/flow
[2]: https://github.com/facebook/reason