If it's financially viable, I would much much much rather have nice pretty hotel food (that we didn't have to clean up, or worry about storing) than grocery store food.
This.
I'm with Laura on letting the hotel staff deal with setup and cleanup.
And this.
The thing is, any time we have to provide our own anything in a situation like this, we end up adding to the stress-factor. Someone has to organize it and make sure it happens, and while I know that there are many many capable and resourceful Buffistas, do we really want to take that chance? Because if it doesn't happen for whatever reason--miscommunication, someone dropping the ball due to a personal situation, etc.--then we have a recipe for resentment, irritation, and other bad ju ju that I think we would like to avoid. Even if we were all responsible for bringing food ourselves, since most of us are coming from out of town, it adds an extra layer of "things to do" and requires planning about where to get food/drinks and how to transport them. Then there's the layer of "where the money is coming from" that can make things ugly on a number of levels. If everyone was left to do their own thing and just meet later, there's also the chance that some people wouldn't get the message and would end up being (or feeling) left out. I know that we would all have the best of intentions, but...I've just seen it happen before with large gatherings, many times.
I agree we need to keep costs reasonable, but especially with the donation pool set-up, I would love it if the hotel was responsible for as many of those details as possible.
I just really would love everyone's biggest worries at the F2F to be tiara placement, corset cinching, and making sure there is an ample supply of candy necklaces. I would say that was my two cents, but I talked too much. Hope you all see that I'm not trying to be bossy; I really just want everyone to be relaxed and happy on the Prom night.