To prevent the many people who have found themselves with accidental palisade-prisons, why not make the wall reasonably easy to destroy until you manually "reinforce" each section and make it a full wall? And possibly make this option only appear after a few hours or so to make it more difficult for griefers.
It strikes me as odd that something you so easily built a few seconds ago can't be deconstructed short of charging it with a battering ram.