In 2012 alone, there were more than 95 million decisions to classify US documents. The cost of storing these secrets for just one year well exceeds ten billion dollars. We can’t be certain of the exact figure, however, because the cost that intelligence agencies, including the CIA and NSA, pay to house their secrets is – surprise, surprise – classified. (source)
Also, Earlier this year, Congress passed a law which requires the NSA to end bulk data collection... to end the crime which was revealed by Edward Snowden. But still, no pardon. And, really, no justifiable reason.
No one knows this better than John Kiriakou, the CIA agent who reported to federal prison two weeks ago for blowing the whistle on the agency’s use of torture. During an interview at an Arlington, Va., coffee shop, Kiriakou said the time has come for Washington watchdog groups—organizations like Public Citizen, Project on Government Oversight, Citizens for Responsibility and Ethics in Washington, and others—to admit that President Obama hasn’t come close to making good on his promise to make government more transparent and accountable. (source)
Lisa Monaco, referred to Snowden's deciding to tell the truth as a "dangerous decision.
Representing the white house position, "If he felt his actions were consistent with civil disobedience, then he should do what those who have taken issue with their own government do: challenge it, speak out, engage in a constructive act of protest and importantly accept the consequences of his actions," she wrote. (source)
If there were a crime committed, it was by the government. They certainly didn't want everyone to know that the government was spying on them, that would be top secret. Everything is a secret from the government point of view.
In fact, it’s so easy to classify new secrets that government classifiers joke that they can find the authority to classify a ham sandwich. (Ha! Ha! Ha! - but, in fact an Embassy Diner Menu is often 'classified'!) These secrets tend to be permanent. Just last month, the Department of Defense blacked out a fact students learn in US History 101 – that the Cuban Missile Crisis ended with a swap of Soviet nukes in Cuba for the US nukes in Turkey. There are so many new secrets created, and so few old secrets released, that the runaway US classification regime has become a menace to American democracy. (source)
Obama’s failure on transparency includes answers to the “Fast and Furious” fiasco wherein the government gave guns to Mexican drug lords, supposedly tracking both and then they lost the guns and the drug lords. The government doesn't want anyone asking any questions about that.
The fact that someone like Edward Snowden may tell the truth is terrifying and they can't pardon him or others may also decide to tell the truth.