Pornographic content, or in the case of what this post is talking about, is different amongst all countries/cultures.
What one culture may find to be inappropriate may be very different from how another culture defines it.
So, essentially, you'd have to respect all cultures as equally as possible.
Many cultures look down upon, in this case, nudity within the media. Thus, the site has to respect that.
Additionally, as mentioned earlier in this thread, this site is under U.S. law, as it is being hosted within its borders I believe.