Adam: We've discussed this before, so hopefully I am not contradicting myself this time.
I think you could build an excellent course without a bunker.
But I think the same course would probably be better with a few bunkers, just to provide the variety of playing out of sand, pitching over a hazard, driving around a bunker, etc.
Just building no bunkers for the sake of building no bunkers is a gimmick. You should build a hole (or a course) with no bunkers only when you really think the hole or course would be better without them. Really building 18 holes on which any bunker would be superfluous, would be a hell of a task.