Indeed, why would anyone need to defend a keep at all if they have points to keep it regardless? I am sure it will cost a pretty penny to rebuild everything (if that is the case), but that doesn't seem like much motivation if they actually win on a "point basis"!

Taxman

"Any group is weaker than a man alone unless they are perfectly trained to work together."
- Robert A. Heinlein, Starship Troopers