Our reader who wrote that "the notion that there is no looting in Japan is a myth" follows up:
Unfortunately, I can't find any English sources on this, because when I try to search for it I am deluged by a bunch of articles about how there is no looting in Japan. But below I list some Japanese sources and provide brief summaries in English. I also found a YouTube video of a looting in progress (albeit calm looting - the employees just watch as it happens).
As of the 14th of March, Prefectural Police in Miyagi reported 40 known cases of looting. An earlier article (on the 13th - there were 21 cases of known looting by then) quoted a police officer noting that known looting cases were likely only a tiny fraction of the actual looting. He also warned store owners to watch out and protect themselves.
An article from a different source on the 17th reported at least 146(!) cases of looting, including failed attempts that resulted in an arrest. Some of the looting is food, but also people taking cash and brand name clothing. The article also talks about a man at an evacuation center attempting to molest a little girl.
(2) Hoarding/Stocking Up on Supplies
Here is article about how people in Tokyo hoarding food and gas are causing trouble for people in the real disaster areas up north. Here is another article about government efforts to stop people form hoarding:
Here is a report about people fraudulently posing as Tokyo Electric Power employees and visiting homes to trick people into paying for "repairs". Here is more general article about the phenomenon of people doing things like using the earthquake to go to people's homes to scam, saying it was extremely common in the past after natural disasters.