Whether you’re one of those shoppers with way too many grocery store loyalty cards or just a few, swiping those at checkouts could be doing far more than just giving you a few cents off your favorite cereal. Stores like Safeway and Kroger are building up their research on how their customers shop, developing customized pricing on the things you like the most. So is that a creepy invasion of privacy or worth it if you save money?

While some stores have already found themselves in sticky situations by customizing offers based on shoppers’ preferences — for example, Target accidentally tipping off a teen’s dad that she was pregnant before she told him — many customers are welcoming the discounts that sometime are offered just to them.

The New York Times checks out some of the changes going on in the supermarket arena, including one comparison of products that are priced differently based on who’s buying it. One shopper who buys a certain brand of products gets a deal on a 24-pack of bottled water that she doesn’t usually buy, just because she is a fan of their other offerings, whereas her fellow shopper would pay almost a dollar more for the same product.

Offering different prices for customers isn’t a new thing — after all, savvy shoppers who use coupons have been getting cheaper deals in the grocery aisles for a long time. But is it different, creepy or an invasion of privacy for supermarkets to mine your personal data and target you with such deals, or does it matter if you want the best price? It’s up to each shopper, perhaps.

Safeway’s personalization program started in stores this summer with offers aimed at certain customers, and it might even start to adjust prices based on its shoppers’ habits as well. The company seems pretty confident this is the way to go.

“If our consumer information is right, personalization is really a consumer desire right now, not so much a consumer fear,” Michael R. Minasi, president for marketing at Safeway told the NYT.

Some stores like Stop & Shop are testing out a way to offer deals on the spot: When customers scan an item they’re buying using a special app, a deal could pop up for something related in that same aisle. This could be pretty useful — you want hot dog buns? Maybe you also need hamburger buns, too! Here’s a discount.

Feel free to share any of your own stories of customized and personalized deals in the comments — whether they creeped you out or left you feeling satisfied that you could nab a discount.

Shopper Alert: Price May Drop for You Alone [New York Times]

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