So, I have a FB app already, and when people connect I ask for the extended permission "email" and that is all well and good.  I save the email and can get a list of their friends' ids and basic profiles.
I want to know if there is a way for me to figure out which of their friends have allowed their email to be visible to people/friends/public (not my app) and then get that email so I can give back a list of people they can connect to.
So, let's say you have 12 on facebook, and of those 12, 4 have allowed anyone to see their email.  I want to give you those 4 emails because they have allowed them to be publicly/friend visible.  Other than those, I'd have to set up a custom "request permission to know your email" kind of thing.
It seems as though it's not possible, but I just wanted to make sure.
We don't allow access to friend email addresses for obvious privacy reasons. You have to explicitly ask for this from each user.
Facebook Graph API: Have extended permission, need something odd