Hi, John. I'm not the poster, but the way I look at it, everybody has to learn caution sometime. If this guy's lesson costs him just $2k and a little headache, I'd say he got away cheap.
I can think of a number of important business lessons I learned that cost me more time or money. E.g., "be careful picking business partners", "don't start work without a signed contract", or "crazy clients don't get saner". All things I should have known, or could have discovered reading. But had I waited until I had read and appreciated all business lessons, I never would have started anything.
And I appreciate him sharing the lesson with Hacker News. It reminds me of the Despair, Inc poster on mistakes:
http://www.despair.com/mistakes.html
"It could be the purpose of your life is only to serve as a warning to others."
So thanks, eam, for getting a bunch of young entrepreneurs to say, "Hey, maybe I should double-check our fraud prevention."