I think you have an insightful point here. For something like friend recommendations, it seems inherently privacy-violating. And it's a problem Facebook doesn't

I think you have an insightful point here. For something like friend recommendations, it seems inherently privacy-violating. And it's a problem Facebook doesn't communicate clearly how the sausage is made. Like you, I don't believe that they need to be so afraid of the consequences—I don't think people will exploit friend recommendations knowing how recommendations are made.