It's pretty safe to say that the majority of the people investing in schemes, do actually know what they are investing in, but ignore all dangers because of their never ending greed. Their idiotic logic basically is that as long as they get in early enough, they'll outlast the scheme, and walk out with profits.
I have even seen someone on YouTube blatantly admit thinking that Bitconnect is a scam, but still consider it to be a great investment because of how thriving and hyped Bitconnect is.
Hype would translate into more people investing in Bitconnect, and that would mean him receiving his payouts as promised. It's not only selfish, but investing in Bitconnect also means supporting them to operate longer.
Anyone investing in these scams isn't just stupid, but due to how their investment keeps that service up and running, they partly are responsible for others to get scammed, which is the worst part.