Latest / The Retention Marketing Podcast with Fexingo: Email, SMS, and Loyalty for Repeat Customers / How Supermarket Loyalty Cards Became a Data Goldmine
Transcript
- Lucas: So you know that little plastic card you swipe for a discount on milk and bread? The one that's probably collecting dust in your wallet right now? Luna: I have three of them, actually. One for the grocery store, one for the drugstore, and one I think is for a pet supply chain I've never even visited. Lucas: Right. And they all feel like the same thing—scan the card, save a few cents, maybe earn a point. But behind that simple transaction, the supermarket loyalty card has quietly become one of the most powerful data-collection tools in retail. Luna: I've heard that before—'your data is worth more than the discount'—but I've never really understood how retailers actually use that data. Lucas: That's exactly what we're going to unpack today. And I think the best way to understand it is to look at the origin story of the modern loyalty program—which really starts with one company: Tesco in the UK. Luna: The big British supermarket chain. Wasn't their program called Clubcard? Lucas: Exactly. Clubcard launched in 1995, and at the time it seemed like a straightforward gimmick. You spend 100 pounds, you get 1 pound back in vouchers. But underneath that simple math, Tesco had a secret weapon: a data analytics firm called dunnhumby. Luna: Dunnhumby. I've heard of them—they essentially built the modern loyalty data model. Lucas: That's right. The founders, Clive Humby and Edwina Dunn, had a radical idea. Instead of just tracking total spend, they wanted to know what was in each basket. Which brands. Which categories. Which combinations. They convinced Tesco to invest in a system that could parse millions of individual transactions. Luna: So they weren't just collecting 'you shopped here,' they were collecting 'you bought diapers, beer, and frozen pizza on a Tuesday evening.' Lucas: Exactly. And that granular data is what made Clubcard revolutionary. Within two years, Tesco had enrolled over 8 million households. They could segment customers into groups like 'healthy eaters,' 'budget shoppers,' or 'indulgent treat buyers.' And then they started sending personalized vouchers based on those segments. Luna: Personalized vouchers in the mail, back in the late 90s? That sounds expensive. Lucas: It was, but it worked. Tesco measured a 28 percent sales uplift among households that received targeted vouchers compared to those that got generic ones. And more importantly, the data helped Tesco decide which products to put on promotion, where to locate new stores, even which products to remove. Luna: So the loyalty card wasn't just about retaining customers—it was feeding the entire business intelligence operation. Lucas: Exactly. And that model spread. By the early 2000s, every major grocery chain in the UK had a loyalty card. In the US, Kroger launched its Plus Card in 2000, and they partnered with—you guessed it—dunnhumby. Kroger now has over 60 million active households in its loyalty database. Luna: And what does Kroger do with that data that's different from just giving discounts? Lucas: So Kroger has something they call 'personalized digital coupons.' Based on your purchase history, the app or website will surface coupons for products you actually buy, not just generic ones. They claim that households that redeem these personalized offers spend about 20 percent more per year than those that don't. Luna: But here's the question I always have: is this all just correlation? Maybe the people who use coupons are just bigger spenders to begin with. Lucas: That's a fair point. And Kroger has actually done controlled tests. They send some customers personalized offers and others generic ones, and they measure the difference. The uplift holds. But there's another layer: the data itself has become a product. Luna: You mean they sell the data? Lucas: Not exactly sell in the raw sense. But retailers like Tesco and Kroger have created 'retail media networks.' They let brands like Pepsi or Procter & Gamble pay to target specific loyalty-card segments with coupons and ads inside the store or online. In 2025, US retail media spending hit over $50 billion. Luna: So the loyalty program is not just a retention tool—it's a profit center. Lucas: Right. And that changes the economics. A loyalty program that only costs 1 percent of sales in discounts can generate 3 or 4 percent in incremental revenue from brand advertising. Suddenly the math is very different. Luna: But what about the privacy side? In 2026, with GDPR, California's privacy laws, and more regulation coming, isn't this getting trickier? Lucas: It is. And that's actually the most interesting tension right now. Retailers have to walk a line: collect enough data to make the personalization useful, but not so much that customers feel creeped out. Some chains, like Target, have actually scaled back their loyalty programs because they felt the privacy risk wasn't worth it. Luna: Target? I thought they were one of the early pioneers with their REDcard. Lucas: They were, but they've de-emphasized it in recent years. Meanwhile, Amazon enters the picture with Amazon Fresh and Whole Foods—they have massive data from Prime and their credit cards, so they don't even need a traditional loyalty card. They already know what you buy. Luna: So Amazon's advantage is that they collect data across so many touchpoints—shopping, streaming, reading, voice—that a grocery loyalty card is almost redundant. Lucas: Exactly. And that raises the bar for traditional grocers. If you're Kroger or Albertsons, you need to offer something compelling enough that customers voluntarily hand over their data. And that's where the next generation of loyalty programs is heading. Luna: What's the next generation look like? Lucas: A few trends. One is dynamic personalization in real time. Imagine you walk into a store, and the app instantly offers you a discount on the cereal you bought last week but haven't repurchased. Another is coalition programs—where one card works across multiple retailers, like Air Miles did in Canada. Luna: Coalition programs have been tried before. Didn't they struggle? Lucas: Some did, because the data-sharing agreements got messy. But recently, startups like Upside and Fetch Rewards are creating digital-only coalition programs that work through receipt scanning. You upload a receipt from any store, and you earn points redeemable at multiple merchants. That gives them a cross-retailer view of spending. Luna: So the future might be that we don't carry a dozen cards—we just use one app that tracks everything. Lucas: That's the vision. And the data becomes even more valuable because it's not limited to one store. But it also raises the privacy stakes even higher. If one company knows you bought diapers at Target, then later a bottle of wine at a different store, they can infer a lot about your life stage and habits. Luna: And that's where consumers might push back. I mean, I love getting a coupon for something I actually want, but I don't love feeling watched. Lucas: Right, and that's the central challenge for retention marketers in 2026. How do you deliver personalization that feels helpful, not invasive? The programs that get this right—that offer a clear value exchange—are the ones that will build long-term loyalty. The ones that overstep will get abandoned. Luna: Short question: is there a supermarket loyalty program today that you think nails that balance? Lucas: I'd point to the one that started it all: Tesco Clubcard. They've evolved from paper vouchers to a fully digital app that integrates with their delivery service. You get personalized offers, but they also have a 'Clubcard Prices' scheme where loyalty members get lower prices on thousands of items without any coupon clipping. It's simple, transparent, and the value is immediate. Luna: So the lesson for marketers is: don't make the program complicated. The best retention tool is one that customers actually understand and use. Lucas: Absolutely. And the companies that treat loyalty cards as a data extraction tool without giving real value back—they're the ones that end up in the dustbin of marketing history. Luna: Well, I'm going to go check my wallet and see how many of my cards actually deliver. Thanks, Lucas. Lucas: Good luck. And next time you swipe that card, remember: the real transaction isn't the milk—it's the data.