In other words, even their signup page contains a scam, designed to steal your friends list. And I'm supposed to trust this site with anything? Fuck no.
I agree it's a good marker for "This site probably shouldn't be trusted with personal data" though.
Then why the heck does it ask for a password?
If I use FB login, the primary benefit is not having to track another password.
I think your definition of scam is a bit off...because every app in the app store would be qualified as a "scam".
Anyway as I can see that you failed to read for comprehension I must reiterate that allowing next-door to read your Facebook profile in no way authenticates you to the site, nor does it provide them with your profile picture.
If you're the first person to login, the site will get an empty list. Only the set of your friends who have previously used the service, will show up if the service queries fb for your friends.
That was confusing and I considered stopping. I went through with it anyway, but that part was strange. Why do you do that?