These have been around for a long while, I assume they've cropped up as some bored hack has googled 'Hitler' on his birth date a few days ago and come up with an easy few lines of 'shock horror!' copy. They're kind of within the remit of those 'collector' ones from Dragon etc.
Dragon Models Limited --- Action Figures
Which I know some on here collect.
There is a whole series by one manufacturer on 'War Criminals of the 20th Century', you always see some for sale at Beltring. To be honest the Himmler one had us in hysterics, they're a reflection of pretty harmless nerdishness (something we're all just a little afflicted with) rather than any threat to the morals of our youth... The prices alone mean they're not for kids.
Cheers,
Adam.