Unlike any other business or homeowener in which we go out and buy insurance, the Watchtower self insures itself.
Each year all congregations sent a check through the WEFTS system for $4.5 for each publishers they have. This money goes to the Watchtower, and is kept as KHAA or Kingdom Hall Assistance Arrangement. Any time fire, vandalism, or mishaps happen the kingdom hall supposedly sends the bill to the Watchtower, and they will help with this bill (of course all labor will be done pro bono through regional building committe)
Since all congregations send this money, they are all sharing in the risk. The watchtower collects this $$$$ and uses it. So this is the reason why they don't let kingdom halls be used as shelters, or to help the public. Any unneccesary use becomes a risk of insurance request, and they would have to flip the bill.
Nice way of getting $$$$$$$$$$$, and keeping in the family
I will later discuss TOAA to anyone interested (traveling overseer assistance arrangement)