That's interesting but this privacy policy also says that is for machine learning technology purposes and that some human interaction is required, in addition only few employees have chess and have to go through background investigation in order to have access to this data set of accessing Evernote information as well.
It's a little scary to think someone out there is reading your private information, but isn't Apple, Google, Uncle Sam doing the same thing. Now days in the age of the internet nothing is completely secured, no matter how many layers of encryption it has.
In my case for storing more private information such as internet logins, bank account information, and so on... I use an app called "Password Plus" from DataViz, and even that data I know is not completely safe. Then again Google knows all or most of these password via Google Chrome since most of these login passwords are stored in the google Chrome browser.
So I wouldn't worry much as long as you're not storing social security numbers, or other logins such as bank accounts and or other sites you wouldn't want wondering eyes to look into.
I also wanted to cleared out that the plus upgrade is $3.99/month not $7.99/month as I had previously stated.