Al, it's not that no one wants to play along, it's just that reality can be scarier than anything a person could ever imagine. You bring up Vietnam; I would wager that any soldier that saw combat there would welcome the thought of clumsy, mindless zombies chasing them instead of living, breathing, thinking foes. And Katrina? What of the horrified survivors forced to endure the images of their neighbors, friends, and family being swept away by the overwhelming force of nature? A total feeling of helplessness. Even just trying to think about what survivors must have felt would seem to do them an injustice and simply fall short. TEOTWAWKI threads are meaningless unless using contexts that are at least tangible.
Absolutely no offense meant, Bro. Just my opinion.