I am not sure whether this question is serious or not - the meaning is so obvious that I would have thought that even a 5-year old could understand it. Let's just say that before advocating the harshest and perhaps counter-productive conditions for offenders people might reflect that one day circumstances may result in them being in the same situation.
Well, that's one interpretation. Another would be that sometimes people find themselves in bad situations that they have no control over. And we could all find ourselves in that situation but for the grace of God. Being incarcerated (counter-productive or not) due to money laundering (or any other crime) doesn't quite fit the bill. Self made decisions tend to control that one.
How can so many adults go along with this? An evil thought usually stays inside someone's head. Convincing loads of others to go along with it is difficult.