> just to watch Zuckerberg reveal something I won't use
I think you're overlooking the value. It's not about going for a keynote or being entertained/catered to; its about the interaction. The ability to talk to the people that've built the tools you are using is extremely powerful. Would you rather talk to an expert on a subject matter, or post a question on SO and hope someone has had a similar experience? This is just one of the reasons why conferences like this are "worth it".
Personally, I would rather that people post their questions - and then receive the answers - somewhere that's easily searchable, so that when other people have the same questions they can easily find an answer. There is certainly value in increasing the number of experts, though, so perhaps that's what you were pointing at.