I do see where you're coming from, and I understand and share many of your frustrations. Yet, in the context that this is taking place, I would prefer to see loyalty and commitment to the club as less of an obligation, but more of a selflessness I would admire and respect but not demand, even of a player like Zambrotta. In that sense, the justification is there. I don't appreciate the request to move to Milan, and even less so the verbal outburst, yet it is beyond me to condemn him for it. I did expect more of him, but I do not demand it. My stand is not entirely different from yours, indeed I do feel likewise to a certain extent, but I choose to view the actions of Del Piero, Nedved, Buffon and the others as a positive rather than vilify the ones that left. The two may not be mutually exclusive but it passes fairer judgement to take sentiment out of the picture; fact is, we did do the players injustice; whether their sentiment for the club affects their decision, for better or worse, is secondary.
About Balzaretti though, I'm unsure about drawing the conclusion of him staying making him a better person than Zambro was. From the perspective of a relative newcomer to the team, the relegation and mass exodus represents far more of an opportunity for Balzaretti to shine, whereas Zambrotta had alot more at stake. Its therefore unsurprising that many of our fringe players have opted to stay now that they relish the prospect to break into the first team unhindered by the bigger names on the roster, now gone to greener pastures. I'm not disagreeing with you on this point, just that it seems a tad hasty to draw a conclusion like that TBH. Cheers.