It's obviously real history to the people who care to go. Now I understand that my comparison is a bit extreme and they clearly aren't equivalent, but you treated it as a mere "information session" which I think we both know is obviously not the case as well. I will grant you that in the grand scheme of things it's not as important as a park opening, but I think Disney Geeks in 10 years who were not at these unveilings or imagineer presentations may be jealous of those who were there. I could be entirely wrong, though, and this could go down as inconsequential.
As to your second point, yes, scarcity does play a part. However, if the spaces available are not artificially scarce, what does that matter? Although neither of us could say for sure, I think it would be safe to say that less than 50% of those who sought tickets were able to acquire them (I'd even say less than 25%, actually), given that, it would seem to me that if this event is profitable for Disney, and it would be feasible to open more spaces, Disney would do it. It also says to me that despite any claims that there isn't enough value in these events to justify the price tag, enough people are finding value to justify it completely. If spaces at these events aren't artificially scarce, the best way for Disney to reconcile these problems (at least in a free market) would be to raise the price. However, then you all would be complaining that the prices or "ridiculous" or "unfair" or some other crap.