Yes, I understand your point. I didn't want to share the user profiles with non-users. I also haven't looked into how easy it would be to harvest profile pictures and profile data. Any thoughts on this?
And yet, if someone wants to harvest profiles, they'll just sign up with a fake/throwaway email address, while legitimate users have to give up real information to do the same.
Of course, it's very hard to prevent any malicious use of the profile data.