And if you've ever turned in a health insurance claim, then anyone who wants it can get your entire medical history.
The loyalty cards are just a way for the stores to bring their data-mining in-house. They were getting it all from your bank/credit card company before, this just makes it more economical and more comprehensive for them.
Honestly I don't care if they know that a 50-year-female from my zip code who buys organic parsley sometimes buys store-made cookies, too.
I'm a lot more concerned about who has access to my medical records. But there's nothing I can do about that, short of paying cash for all of it and choosing a doctor who doesn't participate in HIPAA... of whom there are very, very few nowadays.
Speed comes from what you put behind you. - Judi Ketteler