Whether it be Google or any other organisation when it comes to collecting data they are all the same, being concerned about what they have about you as an individual is a bit late if nothing else, Microsoft were collecting data years before Google were about and people were concerned then. It is a concern but unfortunately the only way to ensure that nobody can collect data regarding you is not to be online.
Data was collected on individuals before computers were about, even if you do not have a pc and do not go online companies still collect data about you. Your credit card company watch your spending pattern and send you advertising about any products that match up. Your local supermarket watch what you buy and send you advertising again to try to get into your wallet. Data is the most valuable commodity but the only way you can get away from supplying it to some organisation is to go and live in a cave somewhere and live on bugs, which may suit some but if you want to live in todays technology based environment then you will have to put up with it.