It was decided, when the newest Rules on building Bases were introduced, that Building a POB did not require RP to building and therefore did not require any RP to destroy until it reached Core 2.
There have been many arguments back and forth, over the intervening years, and nothing has been changed.
I can suggest that you put in a Player Request for the Rule to be changed. The Admins may curse, as this is something else to process, but it is something that you can do.
The Admins will, eventually, vote on it and a decision will be given.
Note:
As pointed out by someone in this Thread, the Attackers can just put a quick post in the Attack Thread and achieve the same effect. All this change, if implemented, would do is give the Base Owner some visibility of who has attacked their Base. The outcome would still be the same as they could do this when the Base Owner(s) were not on the Server.
'I would like to be half as clever as some people like to believe they are' Life is full of disappointments, it is how we handle them that helps to define us, as a person