In the chat I usually make a joke to bunch of people.
"You can do ??? by sending your Steem and SBD to me" or "You can secure your password by sending it to me on DM"
People usually laugh at it.
"I'm not that stupid"
But when someone approaches them in DM, giving a link to a Steemit account and saying "Hey buddy, send me SBD so I'll upvote you" - then they do not suspect anything is wrong.
Same people can first laugh to a joke about poor scams, but then fall for a poor scam themselves. As you said, it's the greed.
Lust for money makes them forget to think.
The photo is great btw!