LONDON: Less than one fifth of UK shoppers account for almost three quarters of total retail spending according to a new study which also claims that these 'super shoppers' are increasingly purchasing via mobile devices.

Deloitte, the consultants, undertook the research for ecommerce site eBay and found that just 18% of consumers were responsible for 70% of spending, or some £200bn a year.

In addition, this group was twice as likely as others to shop via smartphone or tablet using options such as click and collect, the Daily Telegraph reported.

"Customers fully expect your store and online channels to be joined up and can have little patience if they aren't," said Tanya Lawler, vice president of eBay in the UK. "For example, they want to collect in store or return via the store, even if they bought online."

This trend notwithstanding, bricks-and-mortar retailers will welcome the finding that even though showrooming is widespread (31%), its opposite – 'reverse showrooming' – is more prevalent: some 34% did their research online before buying in store, The Drum noted.

A separate Deloitte survey of 2,000 adults and 21 retailers established that, in certain sectors, online shopping did not cannibalise high street sales. Thus, 95% of sales of women's dresses online were in addition to in-store spending.

Andy Street, managing director of retailer John Lewis, told the Financial Times that the online-offline divide was far too simplistic, noting that customers who used both channels spent four times more with the store than those using only one channel.

Ian Geddes, head of retail at Deloitte, said the study's findings suggested that "a broad presence across channels can in many scenarios positively influence store sales".

There was, he said, "a significant opportunity for retailers to use a mix of stores and online presence to boost the bottom line, selling at home and abroad".

European retailers, however, remained to be convinced. "If you go to Spain or Italy, you meet resistance among local retailers," said Jacob Aqraou, head of eBay's European division.

Online retail sales in Italy, for example, account for just 2% of the total, compared to 10% in the UK.

Data sourced from Daily Telegraph, Financial Times, The Drum; additional content by Warc staff