In October, internet users always look for the strangest, most inexplicable Halloween costumes to post. Here's one that illustrates how little Americans and the British understand each other, despite the supposedly common language. This costume of a World War II Evacuee was posted at reddit. Some commenters thought it might be a costume from the Chronicles of Narnia films; others thought it was supposed to be Anne Frank. It actually depicts one of the many children who were temporarily sent away from Britain during the war. But the explanation has to do with schools in the UK, which teach history by designating dress-up days.
Well, there you go. Link
Parents get letter informing them that their little darling has to dress up as an Evacuee, Victorian child, Roman, etc.
Time-poor, stressed parents don't want to have to spend ages researching and making said costume when they could be spending their time w/their actual child (or OK watching TV) (this doesn't really apply for the Roman one because that costume is a sheet)
Parents grumblingly shell out their 15 pounds or so. All kids at school end up dressed identically. Costume company laughs all the way to the bank.
Well, there you go. Link
That said, a Nazi outfit would be tasteless.
A WWII era civilian outfit,no.
It is cute though.