I think only way for MLM model to work in sustainable manner is if it is not a pyramid, but a hourglass shape instead... Basically 1/3 goes to upper level and 1/3 goes to new users to give them reason to participate and the person gets to keep 1/3... This is different from unsustainable 200% profit promise of regular pyramid shape MLM models...

That 1/3 one-time reward given to new users will balance out eventually when they need to restock their supplies. Obviously it has to be one-time reward to avoid infinite loop of the hourglass shape. Basically they pay 2/3 of the actual list price of the goods and sell them for 50% profit (2/3 + 1/3 = 3/3, which equals list price).