One very good reason for me to never, ever enter into such a scheme is the same why I would never, ever have a loyalty card. To me it's totally unacceptable th

One very good reason for me to never, ever enter into such a scheme is the same why I would never, ever have a loyalty card. To me it's totally unacceptable that my supermarket chain has a line-by-line record of my purchases, which it then happily sells to the highest bidder. Is the few potential minutes saved really worth the fact that your insurer now may have a detailed record about your booze and junk food purchases?