Yes it is free to join, granted, but really nothing is free. eg watch your inbox be flooded with emails address personally to you, from people you have never ever communicated with. Maybe today, maybe in a month or even a year. – There is big money in selling email lists of opportunity seekers to online marketers.
Next: the free money offered is NOT real money, – it is funny money (see T & C) on site. Along with many other out clauses for non payment in future.
Next: Wait for the request for money (usually affordable amount like $99) so that funny money converted to real money & you become fully fledged member blah blah blah.