Firstly, I think it's a gorgeous dress. I love it, and would totally wear it if I could. Secondly, I agree with all the symbolism going on.
Now, to address the issue of expense that had been raised. (Erm, yes, I'm a costumer/seamstress... why do you ask? ^_^)
It looks simple, yes. And it probably isn't that hard to make. I haven't studied the photos extensively, but let me put it this way. I would know *how* to recreate it easily. 😉 An empire-waisted, sleeveless gown with an a-line skirt. Alright, it's not quite a-line, but it starts out that way where it's attached at the waist (note the seam is covered by a strip of ribbon, love that touch... it helps to diminish the pregnancy aspect of Regency style gowns... and yes, I do spend quite a bit of time watching Austen and Austen-era films, and have recreated some Regency gowns), before being cut very full by the time it reaches the bottom.
The skirt is made out of several layers of silk chiffon, because pretty much only silk chiffon will hang in such a way as the skirt does. This adds to the expense. I'm gonna put in a guess of two chiffon layers, and one lining layer for the skirt. I'd have to check a higher res picture, but I think there may be one layer of silk chiffon over the bodice.
The higher hem in the front is great for Buffy. It's very practical, less easy to trip over, and certainly makes Slayage easy.
So, you're probably talking about 3-6 (depending on how many layers are present) yards of silk chiffon for the skirt, probably half a yard for the bodice, plus about 3ish yards of silk for the lining for the skirt and bodice, plus another lining for the bodice. That does not include ribbon or beading. Another way of adding to the expense is hand-beading, which is quite possible that the dress could have had. Now, add up the price of the silks, the beading, the trim, the notions, and the time spent creating it, plus stuff for a suitable profit, and one very simple dress can easily be seen as expensive. (Of course, if you wanted to reproduce it, you could do it much cheaper using poly-chiffon etc.)
That said, I would someday love to make both this dress and her prom dress for someone... 🙂
And now I'm going to stop showing my costume geekery and bow out. 😉