You could get rid of Facebook signup but incentive your users after the signup to connect their Facebook account for "a better matchmaking" and to not meet their friends or grandma.
It I would also suggest them to import all of their social accounts (instagram, pinterest, twitter) which makes sense since your role as a matchmaker is to gather informations as much as you can.
I don't see link between your comment and the main topic. Plus this is typical french bashing: we french people financially contributed to your PHD, and you're basically saying that we are racist like some policemen who are just fed up with the problematic mass low-skilled immigration consequences.