So when you go online your Tesco page might flash up smoked salmon or baked beans, according to how wealthy or poor Tesco thinks you are. Is this taking personalisation too far?
Certainly Tesco thinks it can make money from it. "Using Clubcard data," it said in a published speech by boss Phil Clarke yesterday, "we would show, for example, offers of our Everyday Value range to price sensitive customers, and offers of our Finest range to more upmarket customers."
Every little helps
Tesco claims it can use Clubcard data to tell it if a customer is more swayed by price or quality. They've already experimented with the technology on mattress sales, seeing sales bounce 10% as a result. However many people like to browse a range of goods. Not just the more expensive - or cheap - products.
So there's some risk to the strategy. Clarke hints that well-off, big-spending customers will be surprised with special offers. "...it means treating our best customers as we would our friends, by giving our staff more freedom to surprise loyal customers with special offers," he says.
Young TurksTesco is also going big on smartphone technology. Interestingly, it cites Turkey as a country that is embracing Clubcard technology. By the end of this year, Tesco will have launched its Clubcard across Turkey on a digital platform and on smartphones by 2013. This will make China and Turkey the first countries in the world to have a digital Clubcard, says Clarke.
"We'll bring together our existing Tesco apps and mobile web (on iPhone and Android) into one app, which will enable users to find their nearest store; add their Clubcard and scan it at most stores' checkouts straight from their phone; order and change their grocery online shop on the go."
This may be the start of the fighting talk Tesco investors want to hear, given the supermarket's dismal performance in the last year. Many supermarkets and retailers already have a vast hinterland of information about their customers at their fingertips. Clarke's plans appear to be building on this. Rich or poor, once you have a Clubcard, Tesco knows who you are - and how much you have.