Being informed doesn't make someone less greedy. It's still greediness that pushes them into it but they're confident about themselves thinking they'd be able to exit before it collapses. You can be informed and still be the most greedy. In fact, if you are informed but still go into ponzi scheme, it means you're the most greedy because you know what you're into but still want to profit from other people's lose. If this is not greedy, I don't know what to call it. It doesn't make any difference whether you're informed or not, it is all due to greed but the difference is those not in informed are acting based on ignorance.
Greed remains the main reason why many people fall for this ponzi schemes, because there is always an outrageous catch that attracts them. More than half of people that get into a ponzi scheme are aware because before they would get to know about that project, someone should have introduced it to them, pointing out that it is potential pomzi scheme.
People do not care about losing their money when they are promised double or triple of their earnings and that's a probelm. There would always be more ponzi schemes in the future and people would not fail to enage in it, even with full awareness. They need money that comes easy instead of investing their time and resources into something that actually counts, this is beyond ignorance for me.