Actually, this is more the standard in the USA, where violence is tolerated more than nudity. In most European countries, the standard seems to be reversed: American television shows are considered extremely violent and not suitable for children, but you can see billboard advertisements for soap featuring mild nudity (anything except genitals, really). Other parts of the world like Saudi Arabia forbid even showing females in print, which caused a kerfluffle when Ikea photoshopped all women out of the Saudi version of their catalog.
The biggest problem, really, is that obscenity filters are oriented only towards Americans, since the USA has the noisiest "church ladies" and Tipper Gore wannabes (man, I am dating myself here!). The rest of the world is either not big enough a market to filter for, or tolerant anyways so there is no need for more restrictions. So the techies just do enough filtering to cover their asses and can't be bothered to actually maintain said filters, since that isn't really a moneymaker.