My son (and I) had watched the Adam Ruins everything episode about diamonds a few weeks ago. A few days later, my wife had him someplace and they were having a conversation with a jeweler (not sure why). During the conversation, my 12 year old son piped up and started telling the jeweler how much of a "scam" the diamond industry was and how certain diamond companies created the idea of engagement rings as a money maker and how a diamond is always marked up way beyond the value.
According to my wife, the jeweler stood there staring at my 12 year old son and could only say "Well, He's right".
I did not see the exchange but apparently it was quite humorous.