I still think it might be an issue of getting staff to cook and serve. If I would be a reasonably qualified cook on my way up the only places I would want to work nightshifts would be big city clubs or night-time bistros. Hotel breakfast isn't nearly as appealing as preparing a 2am caviar snack and the champagne-influenced big tip to follow.
Hotels might really consider either preparing take away Breakfast packages themselves or outsorcing to an external provider based on pre-orders. Hmm, maybe airline caterers...