I guess, but that's basically the same information that you can get through the referer header in HTTP or by A/B testing different print ads. If you put up flyers in a certain neighborhood telling people to visit a URL, and you put up flyers in a different neighborhood with a different URL, then when somebody visits your site you know where they live.
This is of a dramatically different scale from the information Google has for its own purposes.
> "I would be a lot more OK with this if Google were only using that data about me themselves instead of letting anyone with a little money use it too!"
that would be better, but google would still be subject to attacks by adversaries and (secret) subpeonas by governments.
much better would be if they did their analytics on user data in real-time and store only the results while discarding the source data right away.
IMHO this'll end up being one of the most influential research developments of the last few years, but it's only a couple years old at this point and needs a lot of supporting infrastructure (which'll have to be done by people outside of Google - the mothership has no economic incentive to support this) before it really works well.
This is of a dramatically different scale from the information Google has for its own purposes.