I'm reading this thread with interest, as our local FT group has considered hosting a STL Do, and we can't quite bring ourselves to jump off the bridge.
I have organized a number of events, large and small, for other orgnanizations, and I have to say the whiners can drive one nuts.
We did a convention in Charleston this spring, it was lovely, the City is beautiful and the weather was grand, except for one overnight rain.
Of course, someone posted in the forum of this group that she was upset we had done nothing about the puddles in the parking lot of the host hotel!
Our next con is in London. I have instructed the local organizer to remove all puddles from the general London area.