So, you don't think individual players running around with infinite cities, resources, armies, and cash shop items that they did not pay for, ought to be a high priority? And regardless, this issue has been around since the beginning of the game and the staff has not stated anything about enforcement of this rule. They have a long history of taking an excessive amount of time to communicate anything to the player base, better in recent days but if there is no response to it then most players will just assume that they aren't going to do anything about it and more people will start doing it just to be on even footing with those who are already abusing it.

As far logs they already have records of the IPs of those who connect, as well as the all the battle and transport/reinforce reports between cities, and probably all the mails as well.