Its been a long time since I flew with AZ so I'm not sure if they have a formal policy - perhaps ask over on the "Other European" board where there are probably more Alitalia frequent flyers.

As most of the people responding have already mentioned there *are* formal policies on NZ - passengers must accept instructions from the crew, and crew require that passengers remain in allocated seats during take-off and landing. Additionally there are policies regarding those seated in exit-rows - though in my experience nothing to do with "Air NZ best customers" apart from the first x number of rows of economy (shaded green on itn seat-map) are unavailable for pre-selection but just fine at check-in.

Why not just ask at check-in for a better seat? That way, "This guy" might then have been you - just not being scolded.