A post on forums like this is one of the many compulsory activities, along with YouTube vids etc., that MMM users must complete in order to qualify for the Mavro Extra rate of 100% a month, otherwise they're stuck on a measly 30% 
MMM is not just a Ponzi. It's also a multi-level marketing pyramid scheme, with a downline and heavy pressure on participants to promote it. There is no pressure to get a downline, everyone can earn even if they don't have any downline at all but they will earn more if they have a downline since they will be promoted to a higher rank (1K Manager and 10K Manager) with higher % earnings from the downlines. The members of MMM are so blinded by that "no sponsoring" scheme and thats what makes them think it's legit, which even makes it more questionable if you ask me. It's a very clear ponzi.