One of the recommendations of the Page Society's Trust Report (issued in partnership with the Business Roundtable Institute for Corporate Ethics) is transparency. The report holds that openness is one of the foundations of trust.

This is not particularly earth-shattering. The transparency-trust connection is made frequently by PR pros and civil society. Further, the linkage has been documented in research by Dr. Brad Rawlins of Brigham Young University.

But I've been thinking recently about two companies that seem to reject that principle and yet seem to enjoy almost cult status among consumers – Apple and Trader Joe's.

Apple is famous for its secrecy, which is a hallmark of its product development strategy. On that level, it's understandable. But Apple also treats its corporate issues – Steve Jobs's health, its financial outlook – with equal silence. The media and politicians often call Apple to task for this – see PR WeekNew York and Politico for examples. But Apple's fanatic customers seem to pay little heed – and Apple's brand seems not to suffer.

Now comes Trader Joe's – another trendy company with a rabid customer base. A recent FORTUNE cover story uncovered the white-hot retailer's obsession with secrecy.

So what gives? Is transparency less than it's cracked up to be? Or do some companies have a magic elixir that makes its absence less toxic?

It seems obvious that highly differentiated products and services play a major factor for both Apple and Trader Joe's. In more commoditized sectors, I suspect secrecy might be penalized more severely.

But the question I can't answer is this: Have Apple and Trader Joe's permanently repealed the law of gravity, or are they doomed to fall back to earth if they continue to stonewall their way through the next crisis?