Middle-class Brits are deserting Marks & Spencer and The Co-operative Group as top-up shop destinations in favour of the discounters, according to a major new survey of Mail and Mail on Sunday readers.

The survey, which polled 1,500 print and online readers alongside a further national sample of 1,000 people, shows 56% of Mail readers now regularly shop at a discounter, with 39% visiting Aldi and 35% Lidl compared with 20% and 23% respectively in 2009.

The findings, given exclusively to The Grocer, also show a huge rise in the number of different stores shoppers use regularly, up from an average of three stores in 2007 to six now.

Almost half of readers regularly visit two or more top-up shops on the same trip, with 60% of those who top up at Aldi falling into the ABC1 demographic groups.

Worryingly for Marks & Spencer and The Co-operative Group, the figures reveal that despite Tesco, Asda and Sainsbury’s either maintaining or improving their position since 2009, they have been losing Mail shoppers rapidly.

Asked which supermarkets they visit regularly, 31% of Mail readers included M&S compared with 36% in 2009, and 29% named The Co-op (34% in 2009).

When asked what motivates where they shop, quality (74%), fresh produce (72%) and product range (68%) all came significantly ahead of cheap prices (60%).

“The survey shows it’s not just price leading to people taking these decisions,” said Sandro Ruccia, senior marketing strategist for the papers.

Despite the upheaval caused by the discounters in the UK grocery market, the survey also suggests their rise has not meant the death of the big weekly shop. More than 80% of the readers surveyed said they still did a main shop at least once a week, up from 71% in 2009.

“In this era of convenience, Mail readers haven’t abandoned the big weekly shop,” said Ruccia. ”They are cherry-picking at more supermarkets than ever, across a varied repertoire - big and small, from discounters to more upmarket stores.”