Speaking from experience, I can say that documents aren't given a classification simply to "hide" information from everyone.

There are strict rules to be followed if you want to classify a bit of information.

Once you classify something, it has to be maintained and tracked. There is a cost associated with it.

The First Amendment does not apply to classified information, and for good reason. The government does not classify documents simply to hide information from the general populace; it truly is a matter of life or death in many circumstances.

Abusing one's security clearance can result in severe penalties.

I, for one, cannot read the document, as I no longer hold a clearance, and am legally obligated not to read or download it.