Last month, rioting broke out in China during a rash of anti-Japan protests. While those protests got plenty of news coverage in Japan, the country's own protests haven't. Perhaps the networks are worried footage of such protests would further fan the flames in China...
Gimmeaflakeman's thoughts on the rioting in China are worth checking out, too—especially why he thinks there hasn't been violence in Japan. Have a listen.
Anti-Chinese demonstration in Tokyo [Japan Probe]