The folks who freak out whenever a privacy policy is amended or whatever, are to put it bluntly...annoying.
Google is not, I repeat, NOT, going to steal your private info.
If they did, and they got caught, it would be such horrible PR...why would they do that? There is way too much at risk for them to do that.
In the era of cloud services, trustworthiness is the objective of any company who supplies a cloud service. Why would they do the one major thing that would create any distrust? Google is huge and therefore a lot of people are watching them under the microscope.
Google, Facebook, Apple, Microsoft, etc... they aren't going to steal your cloud documents or photos and sell them to the highest bidder. That's ridiculous.
Yes, sometimes the privacy policies make is sound like they are saying they can do whatever they want with your data, but they have to word their privacy policies that way so they can provide you the service without getting sued down the road. They deal in data, and data has to be backed up, moved across servers, etc...and, legally, they have to say they have the right to copy/access your data. It's all encrypted anyway, and no physical person will actually see any of your stuff.