Why should I join your start-up?
voltsteve.blogspot.com
voltsteve.blogspot.com
Maybe I am just the wrong audience?
That's pretty much spot on. The job market for decent developers is incredibly competitive as there are more jobs than there are good candidates.
Generally companies who present at these events are expanding hence the need for more people.
The only way a company is going to find the right people is being vocal about it so I'm afraid you probably won't see the trend change for quite a while.