This particular account may not have turned a profit, but it might over time.Setting aside the top earner on the service (because they're a record label), the second highest earner has earned $29 by buying $70 worth of songs. Third highest: $28 for $64. 4th highest: $24 for $66.
I have absolutely no doubt that with access to their database and a quick query you'd find out exactly what you find out in any MLM: the overwhelming majority of the people lose money. And I have a profound, abiding disrespect for something which is a business model when it is profitable and a consumption expense when it is not -- its not like Mary Kay recruits people with promises of access to wonderful new cosmetics.