For the last, I'd actually argue something.
Namely, it's the job of art, to some extent, to force people whether they like it or not, to question their own perceptions of things. To take a quote from the movie V that illustrates this,
"Artists use lies to reveal the truth, politicians use lies to hide it."
To apply here, art can, and has, made people change their perceptions of morality, and similar subjects. So, I think the key would be to get a popular work(perhaps it became popular for other reasons) that had a prominent anti-villain. We already have this in stories like Watchmen, lets see where else this can crop up.
Namely, it's the job of art, to some extent, to force people whether they like it or not, to question their own perceptions of things. To take a quote from the movie V that illustrates this,
"Artists use lies to reveal the truth, politicians use lies to hide it."
To apply here, art can, and has, made people change their perceptions of morality, and similar subjects. So, I think the key would be to get a popular work(perhaps it became popular for other reasons) that had a prominent anti-villain. We already have this in stories like Watchmen, lets see where else this can crop up.