As for volume pricing it almost certainly does take that into account. Most electronic component manufacturers publish "Budgetary price per xK pcs" which I assume is where most of prices mentioned in article come from. For even slightly specialized parts this number tends to be significantly lower (tens of percent to order of magnitude for some parts) than price given by distributor even for same xK volume discount. Also most significant parts that are used across different Sony products tend to be either insignificant (passives) or manufactured by Sony (or semi-custom parts manufactured for Sony).