I'm thinking that old Vicky didn't even know what a Nazi was. Way after her time.
As to the costume, people are just revealing what petty, PC whiners they can be.
If a kid can go to a party dressed as a condom, a devil, a hooker, a giant joint, or a deranged three-eyed monster, why not as a Nazi?
That's not saying that the Nazis need any fond remembrance, but Stalin, Idi Amin, Pol Pot, Mao, and Saddam Hussein all did things just as bad or worse to humans, hell, Stalin and Mao each ordered 10 times as many people killed as any Nazi, but nobody would have batted an eye if the kid had worn a hammer and sickle or a flock of yellow stars on his arm.
It's all just lip-service for the sake of political defamation.
Petty, petty petty.