This talk of the lack of looting in Japan as compared to New Orleans reminds me of a story Michele once told on FTL about this time when she was in Tennessee helping out during the flood a year or two back, (a flood which was like, the worst in the state's history or something but something else was going on in the news at the time and drowned out the story,) and the local news caught her and her boys on camera and declared them to be looters.
I think I've heard of the same thing regarding Katrina -- that a lot of the so-called looting was actually people helping each other out.
A lot of stereotyping probably comes into play. Few think of the Japanese as selfish looters, but a lot more (at least in America) probably think of black people that way.
If it weren't for endless examples of black folks rioting and looting in other everyday situations, ball games, smashing Korean storefronts in LA, flash mobs targeting convenience stores, etc... then you may have had a point.
During disasters, no one questions, or should anyway, people taking food & water. Truckloads of it even.
People in America do think that about Black folks, and with reason.
Don't forget the white boys who looted golf clubs during Katrina too.