Hoarding top secret material: notes from Mi~Beloved video NSA spy

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Actually, amassing over this length of time, in this amount and these manners can be an ingrained instinct. He might very well just be a hoarder!

It seems that he would have probably hoarded much in a different context anyways. Such instincts could have been useful in a different life form for survival. 

He did say that his intention was to study the material in order to do better at his job, so that can be interpreted as a focus on survival.

After all, he hasn't and couldn't be using all this stuff over so long a period when they are archived all around him, including digital, and physical in the house, the garage the car...

The difference simply relies in what is being hoarded.