Would you just sit there for 3 or 4 days waiting? You, of all people, would find your way out I would think. I would have been walking towards civilization. Just staying there is obviously not the smart thing to do under these dire circumstances.
How would you know which way to head for a passable route out? I think the vast majority of people are doing whatever they can to help themselves. For the people in the Superdome, unfortunately, there probably aren't any options with a higher probability of success than waiting to be bused to the Astrodome. Just doing "something" is not smarter than doing nothing, if doing nothing has a higher probability of success.
As for me, there's no way I'd be living in a place that's a disaster waiting to happen. But I have more options, and more ability to analyze risks, than most of the people who are stuck there.