It works like this:
1. Wow, he made $2,000 with one launch on PH. 2. The product must be a quality product if so many people bought it. 3. I'll give it a try.
Also, MRR's screenshots are creating a network effect on Twitter. The tweets of this character, automatically become more valuable, because he earned, he won.
I think this has started to gain momentum in the last year or two. What do you think?