I was going to buy a book online today. A once-off purchase on a whim. I didn't buy it because the company selling it wanted to "get to know me". This isn't a very interesting story, I know, but a point will be made.
The company insisted that I had to create an account (although it already had my shipping details) to make the purchase. It was vital that I didn't miss out on the features of an account; so vital that I couldn't give them money until I had done it. The company insisted that it needed to know my name, and my phone number, and my address, and my date of birth.
So I walked away.