As the supermarket closes another seven stores customers are told their branch of 40 years will become a Lidl

The sign outside Waitrose offers a “sad goodbye” to Bromley residents who have been shopping in its Sundridge Park store for more than 40 years.

The store is closing in the autumn because the supermarket says it “has been unable to find a way to make the shop profitable in the long term”.

The store will become a branch of Lidl, the German discount supermarket chain that, along with Aldi, is expanding aggressively in the UK and shaking up the status quo.

Bridget Wright, who has shopped there all her life, is stunned by the closure: “Oh my God. I can’t believe it. My husband told me this morning that Waitrose was closing some stores but I was sure our store would be safe because it is always busy and the staff are lovely.”

Facebook Twitter Pinterest Bridget Wright at the Bromley branch. Photograph: Martin Godwin/The Guardian

The 64-year-old likes the German chain too, but she prefers Waitrose with its wine selection and upmarket product range. “They sell duck eggs which I don’t think you can get in Lidl.”

A survey once claimed that the arrival of a branch of Waitrose in a neighbourhood, with its upmarket organic food brand Duchy and Heston Blumenthal range, could add nearly £40,000 to the value of homes. But the retailer, which is part of the employee-owned John Lewis Partnership, is now in retreat, selling off or closing unprofitable shops as it adjusts to an intensely competitive grocery market where low-priced rivals are on the up.

There is clear evidence that snobbery associated with where people shop is a thing of the past in Britain as shoppers seek out the best quality at the best prices. Aldi and Lidl are the fastest-growing supermarket chains in the UK as some of their larger mainstream rivals are questioning their business models.

Sainsbury’s and Asda – the UK’s second- and third-largest supermarkets – recently tried to merge in an attempt to strengthen their hand against the discounters but the competition watchdog blocked the deal.

Facebook Twitter Pinterest Kylie Day at the Bromley store. Photograph: Martin Godwin/The Guardian

Even though she has an emotional attachment to the store, Kylie Day thinks Lidl will be a better option for local people struggling to get by on low incomes.

She says the Waitrose store suffered from a “lack of custom” even though there is little competition in the vicinity.

“I’ll be sad to see it go as I’ve got memories of coming here with my nan …but I think Lidl will get more shoppers because of the prices,” she says. “I think the older generation have moved on and there is nobody here to spend money: younger people haven’t got it.”

Aldi and Lidl are now bigger than Waitrose, which is only the eighth biggest chain in the UK with 344 stores. The two discounters ring up one in every seven pounds spent on groceries in the UK.

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After making inroads during the last recession the German chains have gone on to transform the way Britain shops. Last Christmas – a time when Britons traditionally take their custom to more upmarket stores such as Waitrose – two-thirds of UK households visited Aldi and Lidl, handing them their biggest ever slice of festive spending.

Waitrose says the decision to close seven supermarkets, with three – Bromley, Oadby in Leicestershire and Wollaton in Nottinghamshire – being sold to Lidl, is not a sign it is throwing in the towel. It is ploughing cash into its online grocery service as it prepares to end its long-term distribution deal with Ocado next year. It says it will compete with bigger rivals by making its stores more exciting places to shop, with the addition of sushi counters and wine bars, rather than trying to become bigger.

Facebook Twitter Pinterest Peter Dowse at the Bromley store. Photograph: Martin Godwin/The Guardian

Lidl, the smaller of the two German chains with 760 stores around the country, said last month it would invest more than £500m opening new shops in London. It is also building a new headquarters in Tolworth in south-west London to house 800 staff.

Putting his Waitrose shopping bags on the boot of his car, Peter Dowse has not heard that the name on the door is going to change but says his main reason for using the store has been convenience. “I’d prefer it if they kept it as a Waitrose but I will probably keep shopping here,” he says, adding: “If it goes too downmarket I might think otherwise.”