Google is Watching You...Like You Asked Them To

I don't understand the uproar over the fact that Google Android phones collect location data. I'm not saying it's right that they're doing it, but it's not like Google made any secret of it. I've had to do the initial setup on quite a few Android phones and whenever I'm setting up my phone for the first time, I have this option pop up:

"Allow Google's location service to collect anonymous location data. Collection will occur even when no applications are running."

You have to have a check in the box next to it in order to use any of Google's navigation services. So what's the problem? Is nobody reading these things? If you didn't want it to happen, you shouldn't have checked the box.