The value is in networking (meeting other like-minded people who can afford the $8,500 price of admission).
You're probably right, although I'm thinking that there must be more efficient ways of networking. I was considering going to Google I/O this year for the networking, but have decided that it's probably not worth the $3k it would cost me.
Perhaps someone needs to come up with a social networking tool for people like HN readers.
The sense of smugness you will achieve is worth it to some people.