It is my opinion that if these images of evil doers are suppressed, that people will tend to forget these atrocities were ever committed. "out of sight, out of mind" as they say. It is good to keep these images alive in the minds of people who weren't there, to help shed light on the historic past, recent or ancient. It is important to remember them so as not to let it repeat. Also, I'd like to add that these particular wax figures (all of them for that matter) are works of art and should be respected as such.