A problem I see with monetization: most transaction systems are easily traceable and not really anonymous (Paypal) – closed source, while they rely on multinational mega cooperations (Paypal; Alipay; …). So to that end your account & character becomes easy to data-mine for that mega-co.

On the other hand: Any social network that allows for anonymity and new sign-ins will get spammed with Propaganda and AstroTurf in the long run.