I agree that most companies want data for no good reason. Perhaps they think it will be useful for marketing or to sell - I do try to restrict what I give out. Last night we went to a pub restaurant (which I had booked online) and today they wanted a review. I was prepared to do so until the feedback form asked for my postcode. They wanted to know where we were from. The form required it. I could have put in a false one but decided to ditch the feedback all together.