It could simply be that the network isn't used as much over there. Martha's Mirror certainly seems to fall on the antisocial side -- or she keeps to herself, anyway.

"It could be that they don't use it as much because there are no events there. A lot less to talk about, I would imagine." It could be for other reasons, too. Maybe the Queen of Hearts doesn't want them overdoing it. Maybe they noticed Chihiro's security breach and decided to be more careful with what they say over the network.

Martha turns her attention from the screen back to Chihiro. "Have you gone through all of it? Is there anything useful that's ever mentioned, or is it mainly just mundane conversations?" Strange, to think that the Mirrors might get bored the same as they do.