Your search history, data, information is their buisness you are worth good money to them regardless if you click a ad.
I would go as far as to say give me a piece of my pie if used my browsing habits in a study. I would like to know if my search habits caused an increase in sales for the company but thats just wishfull thinking, always think the worse right now, google did have a motto do no evil, however since the new admisteration, copyight czar, and crazy IP, DMCA legistation floating around these assholes might just turn there back on that, and by the way that slogon was used before it became the giant it is today. They control a lot on information and Pay a lot of people wages. Assume teh worse... that they will sell or use browser statistics against you and possibly in the future they may turn over your browsing habits and compete search history, if not already your nosy ISP. cough comcast. Not that your data is safe on there severs anyway, its out of your hands and in theirs and who knows if the NSA or other agenices dont have some type of tap into that gold mine. C-mon im sure the chinese govt and baidu are best buddies. Maybe google needs more transparency, its nice in all with all the open source projects they help, but I would like to know what thier spider crawling software is doing to collect my info and whos hands it touches.