LONDON: People who shop online for groceries tend to spend less than if they did their shopping in-store, as they are less likely to buy products on a whim according to a new survey.

Digital research specialist eDigitalResearch polled 1,154 online grocery shoppers and found that 29% felt they were less inclined to make impulse purchases when shopping digitally. In contrast, just 7% said they made more impulse buys online than in-store. This gap, said the company, highlighted a potential threat to supermarkets which are busy encouraging more people to shop online with money-off vouchers.

"The growth of online has the ability to drastically hamper supermarkets, retailers and suppliers," explained Derek Eccleston, commercial director at eDigitalResearch, arguing that as the online grocery market grew, overall spend would shrink.

Supermarkets, he said, needed to understand a new breed of grocery shopper – how they shop and why, as well as what makes them buy what they do – in an effort to encourage online shoppers to spend more.

An example of the how comes from Peapod, the US online grocery store, as vice president and managing director Tim Dorgan outlined to a recent conference. "The way people order is: they go on and start an order; they will come back for two different other sessions before they actually finalise the order," he said. "They go on early to secure their delivery time, so there are three or four sessions."

As well as spending less, online shoppers are also more likely to switch brands than those shopping in-store. In eDigitalResearch's survey, just 10% said they always stick with the same brands for particular items, suggesting that there is a huge opportunity to influence people's purchase decisions and disrupt their journeys online.

Price is obviously one driver of brand switching – and Dorgan noted that Peapod's relatively wealthy customers were not immune to the appeal of a bargain – but eDigitalResearch said that loyalty card promotions, search positions and product images also all affect how people shop online.

Data sourced from eDigitalResearch; additional content by Warc staff