The cashiers at my local Safeway are constantly shocked when I tell them that I don’t have a Safeway card, since I’m giving up a significant discount. Even though our information is everywhere these days, I just have a weird feeling about having my grocery purchases tracked, gathered, and sold. My addiction to the delectable chemical concoction in Safeway Select Sugar Free Popsicles is no one else’s business (except now, I suppose, yours.) And I’d never even consider using my fingerprint to checkout at a Amazon-owned Whole Foods. They don’t even know I’m a Prime member. Maybe my concerns are warranted. Jon Keegan with a very detailed look at what you’re trading for a discount. Forget Milk and Eggs: Supermarkets Are Having a Fire Sale on Data About You.