Nah, Facebook groups are full of people that don't really know how to play the game well and will rage too much. People who are serious about getting a team will make more of an effort to get it in more 'professional' places.
I'm from Portugal, and I hear a lot of guys that make teams by picking guys watching zorlak streams. Because who's watching those streams surely wants to learn. I don't watch him, nor have I ever been interested in making a team in such way, but I think it's a better approach than Facebook.