I've seen this before actually, so uh... Please don't fix it i guess?
A lot of servers rely on this for inactive who have been hogging resources or equipment so it can be cycled back in.
One server I was on the only miller quit and it was days before we could get another star. Thankfully, when his property defaulted over to the government they picked up the claims and all the equipment stayed.
I know it might not be intended, but it has been a very useful feature, especially if you aren't going to let admins access void storage. It will greatly limit the ability of a troll to screw a smaller server over.
It seems there is an issue when unclaiming via the map, which is going to be fixed.