Using Google Analytics is simply very useful for yourself in order to optimize your website and to see how people come to it. Its a must have for a webmaster starting to get decent traffic!
No matter what is Google collecting about our website traffic, specially if it's not breaking any of their rules
Google knows everything about our sites and our searches. Have you seen Google Flu Trends? They know a lot of stuff and have it all recorded.
I know what you mean. I thought of this as well. But it does provide some nice information that I really appreciate. Therefore, I will use it for a while.