So far I haven't seen people who invest in ponzis getting tagged with a negative feedback so your argument of "people who decides what to do with their own money" doesn't make sense to me at all.  
What I see is that those people who openly advertise or in other form promotes the ponzi are the ones who get negged. Which they actually deserve since they are helping to promote a scam and at the same time they are openly robbing other people of their money jut to get a cents of commision and to save your own deposit.