Very good points and I am learning new things with regards to corporate socio-cultural behavior and policies. On the other hand, other Japanese manufacturers acknowledged certain issues with their products such as the example mentioned with Toyota, Fujifilm with the X10 bulb issue, Canon, Sigma. etc... I think it's corporate specific policy rather than a Japanese cultural thing. Here's what Hogan says:
"When Canon users complained about oil on the sensor, Canon's response was to offer a free inspection and cleaning to anyone who had the problem. That's probably the right response, since the issue is caused by sloppy manufacturing. Nikon will usually clean an oil-stained sensor for free (after you ship it to them at your expense), but they have made no acknowledgment that such a thing can happen, let alone an apology and specific course of action a user should take, as has their competitor."
As for "why", it's simple. If you buy something new from a reputable brand name and it's still under warranty then you expect the company to handle such issue. I am not blaming them for the issue, manufacturing mistakes happen, however, customers deserve to be taken seriously. They deserve that Nikon covers shipping and cleaning for the sensor free of charge. All people are asking is acknowledgment. If they don't acknowledge it then you'll have angry people swarming forums and social media with a vengeance and each person will add some spice to his story and suddenly a small issue (which is common in every SLR from any brand) would turn into an overblown topic across the internet. IMO, it's not a QC mistake, it's a public relations and managerial disaster.
In other words, why blame the people who sign petitions rather than blaming the source of the issue?! Let the people express their well justified disappointment, they brought it onto themselves. If petitions don't help, then at least those affected will offload their anxiety.
"Are you saying that high performance cameras are for anyone? They are not but many buy them thinking that there is no difference between more general purpose cameras and think the camera will compensate, when actually just the opposite is true."
High performance cameras are for anyone who can afford them. Does that make them better photographers? Maybe not, but that's irrelevant here. Ferrari covers manufacturing mistake regardless of how good drivers their customers are Besides, the D600 is directed towards enthusiasts rather than pros IMO due to it's build and price.