No, it’s not against the rules. And no, it shouldn’t be against the rules. It’s a serious problem, but not one that can or should be solved using the official server terms of conduct.
I assume you’re referring to this:
This has nothing to do with refreshing and decay. It’s inside the “clan and personal responsibility” section and it’s not a rule in itself. It’s an explanation of why you’re included in disciplinary measures that are handed out to the whole clan, even if you’re not being active in that clan. And it’s also an advice for those who want to avoid that particular problem.
We need a new gameplay mechanic to help with this. Dennis has confirmed, during his AMA, that this is “on their radar” and “definitely not off the table”.
I think it would be best if they implemented some kind of an upkeep system, something that has been periodically suggested on the forums. The latest discussion (that I’ve seen) on an upkeep system can be found here:
Feel free to contribute there, it’s stalled a bit 