You're hired by company XYZ and the boss tells you that it is critically important that you never let anyone outside your immediate department see the XYZ Procedure Manual - - so important that you have to sign a sworn statement that you won't do so. He makes it clear to you that breaking this policy will result in immediate dismissal. You agree to this condition of employment and sign the statement.
A good example. People, you need to realize that "working at Apple" is not a homogenous statement, just because you carry an employee badge doesn't mean you are privy to everything -- at ANY company larger than a handful of employees. Apple is a big company with thousands of employees, and each employee has a list of things they can and CANNOT access.
Where do YOU work? If you popped down to HR and asked to see all the employee files and salary reports, would they let you? If you went down to the test labs and asked to give the new prototype a test drive, would they let you? If you're trained as a burger flipper, would they let you take cash for a shift? "But I work here!" isn't an excuse to see everything your company does...
At my company, there are 3 levels of security clearances, you need to have specific access programmed into your badge to let you enter certain labs, and there are dozens of different labs each with teams working on different projects. Certain things are so sensitive that you have to sign into a special locked secure area just to HAVE MEETINGS to DISCUSS them, and you certainly can't leave documents about them lying around. There are shredder boxes on each floor beside the printers to dispose of sensitive documents.