Automatically tracking shared url from Facebook, as GA already does

It seems to me as your assessment is correct. I did not think about it that way.

So in your opinion, is there a way that I could configure this kind of report on my own pretty easily and get the same kind of info?

Very helpful. It seems like this is really just an Entry Pages (or Entry Page URLs) report built around a segment defined as "Page Views where Referring Domain = facebook.com." It's not doing anything to label the link as best I can tell; it's simply showing the landing page since that should be the same as the link. Is that a fair assessment? 

This is what I mean : the actual url that was shard on Facebook. I know my referring domain is facebook.com. What I am interested in is which link shared on Facebook truly generated visits. Here is a print screen of what GA does. Let me know if there is already a way to get that info or if you have any more questions.

Have a nice day!

Pier-Olivier, do you simply mean the full referring URL? Can you give me an example so I can better understand the request?