A permanent creative server would be a HUGE problem to maintain with the same plugins as survival. Think, if everyone had diamond blocks and fly - practically all the nearby places that are anywhere at all would be claimed, yet you could not get rid of land claiming because of tnt - Everyone would have infinite tnt with which to grief to their heart's content. Even on server where tnt is disable, there are plenty of other ways to grief. A creative server would not be practical with the current plugins, and it would take too much time and effort to find/make a whole new set of plugins to make a creative server even practical, let alone in working and maintainable condition.