why would I be more scared of the Chinese knowing that I purchased a book from Amazon any more than I would be scared of the NSA?

The NSA is not legally allowed to eavesdrop on US citizens at random. There is nothing to stop the Chinese doing so.

Well, the NSA wouldn't bother to steal your credit card.

Depends on what you are purchasing. If you have no plans to visit China, probably don't care. But if you are planning to visit China, be aware both the NSA and China will take an interest in you

No idea why, if you didn't live in China why you would be concerned what china knew about you.

The NSA hauls you off to jail?? What exactly have you been buying from Amazon??