That will be £42.40,’ says the checkout assistant as I pack my Tesco shopping into bags.
It’s more than I’m expecting but, as everything seems more expensive these days, I don’t question it.
I scan my Clubcard as I go to pay and suddenly the price drops by nearly a third to a total of £29.22.

Discounts that are not so good: If you don’t have a Clubcard, this basket of shopping will cost you 45% more at Tescos.
The assistant smiles when I say that my surprise was expressed. ‘You don’t get any of the deals without the Clubcard any more. People really regret it when they don’t use one,’ she says.
As I leave with my trolley, I can’t help but think this doesn’t seem fair.
While customers should be rewarded with benefits if they use a loyalty card and share their shopping data with retailers, they shouldn’t be penalised if they choose not to, says consumer expert Martyn James.
‘Any business with a loyalty card should give people the option of opting out of their data being collected without losing discounts,’ he adds.
Tesco Clubcards have been used by over 20 million Britons. These cards allow customers to earn points, which can be converted into cash-off vouchers.
In return, Tesco gets the details of what you buy, how much you spend and how often you shop — information vital to the retailer in helping it to understand its customer base and maximise its profits.

In fact, this data is so valuable that last month Tesco announced it was now a ‘media owner’ and would use the information it receives from Clubcard shoppers to sell advertising space to brands.
It is doing this via a ‘media and insight platform’ operated by its wholly owned subsidiary Dunnhumby, a London-based ‘consumer data science’ specialist.
On the firm’s website, a section aimed at attracting advertisers to the Tesco scheme explains that it can use Clubcard data to ‘build an exact profile of your best customers, and what matters to them most’.
Furthermore, it says it can ‘target customers from sofa to store, wherever they are and whatever their mindset’.
Brands can also be assured that it tracks what customers buy when they view specific advertising, in order to make sure they have an influence on how we purchase.
Tesco will sell advertising space in stores, on its Scan as you Shop app and website; via marketing emails and on Clubcard voucher mail letters. This allows shoppers to be targeted with offers and coupons when they get their vouchers.
But what if you don’t want the supermarket to profile you and use that information to target you with advertising?
Previously at Tesco, you could simply opt not to use a Clubcard if you didn’t want to share your data. You would miss out on earning points.
But in 2019, the supermarket introduced Clubcard Prices — a system where discounts are available only to Clubcard shoppers. This is now available nationwide. To access these special offers, you will need a Clubcard.
Without a Clubcard you’re likely to be out of pocket, as the standard prices of many items are surprisingly high.
For example, a 500g tub of Lurpak slightly salted spread costs £2.75 at Tesco with a Clubcard but £4 without.
And for a 100g jar of Nescafe Azera Americano coffee, you would pay more than double at £5.49 without a Clubcard, compared to £2.74 with one.
My 15 items cost £29.22 with a Clubcard; £42.40 without. And when I looked up how much the same basket of goods cost at other supermarkets, I found I could have bought them for a total of £32.07 at Asda, £34.58 at Morrisons and £35.30 at Sainsbury’s.
This means that Tesco’s prices for items without Clubcard are about 25% higher than those charged at the Big Four supermarkets.
However, the Clubcard did give me a good deal on my shop — it was about 14 per cent cheaper to buy the goods at Tesco with a card than the average cost across its competitors of £33.98.
My shopping experience would have been 45 percent more if my credit card had not been scanned or I chose to skip it.

Tesco Clubcards have been used by over 20 million Britons. These cards allow customers to earn points, which can be used for money-off vouchers
This was just a sample of 4,500 Tesco products included in their deals. Comparatively to other major supermarkets 60 percent of my items were higher or more expensive than when I was shopping with a Clubcard.
‘Customers shouldn’t have to pay a premium to keep their data private,’ says James Daley, of consumer group Fairer Finance. ‘You used to be awarded benefits for sacrificing your data. Now it looks like you have to pay extra if you value your privacy.’
James Walker, of consumer data action website Rightly, describes the situation as ‘daylight robbery’. He says: ‘Tesco has recognised the value of the personal information it holds on Clubcard customers. The downside for the customer is that they are subjected to bias and the overpricing of services.’
Tesco claims customers can modify their marketing preferences through their account. Targeted marketing isn’t a requirement to benefit from Clubcard offers and points.
But when I logged into my account on the Tesco website, I could only find an option to opt out of receiving ‘marketing offers or promotions from Tesco stores by email, text message, phone and post’. Targeted marketing is not mentioned in the store, on the website or via smartphone apps.
Loyalty card holders may also receive special discounts from other retailers. Superdrug has a rotating selection of deals only available to its Health & Beautycard holders.
And in September, Sainsbury’s introduced a scheme called My Nectar Prices, which offers discounts on selected goods to those who have its Nectar card and use its SmartShop phone app to shop in store.
However, unlike Tesco’s loyalty cards, customers can still benefit from discounts and other offers at both stores.
A spokesman for Tesco says: ‘We make it easy for customers to make choices about the data they share, and you can have a Clubcard and benefit from Clubcard Prices while choosing not to receive targeted marketing.
‘We only ever use data customers have agreed to share with Tesco, which allows us to personalise our offers. So, for example, if you’re looking for a bottle of red wine for Christmas and there’s a great offer on the wine you usually buy, it’s helpful for us to let you know.’
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