I wouldn't want to be paying the fuel costs for the new A380. Nor would I want to be going somewhere where that many folks would like to arrive at the same time.
Come on, could you imagine deplaning in a major tourist location with that many other folks clutching their tour guides and toting their digital cameras itching to get a snap shot of any of the toursim icons?
There is big, and then there is the behamoth. Think of it like the Hummer of the Sky. Sure, we can build it, and we have the technology, but is it a good developement? Like the proliferation of prefab, fiberboard housing developments that are eating up our open space - named for places they've replaced (e.g. Elm Grove Homes, or Abbeywoods, etc...): Just because it can be classified as development doesn't mean that it is.