To go back to your original question beyond the more general, I would think that taking 3 or 4 would indeed be sort of logically frowned upon, but taking one almost certainly would not. If your wife takes one, when she finishes it, the cabin crew will undoubtedly gladly refill it from their big bottles. I don't take food and drink from lounges with that one exception: one small bottle of water, which makes a hell of a difference during the flight.