Counterintuitive Shopper Habits

One of the joys of being a researcher is having your expectations confounded. You’re learning all the time.

We partnered with a client to explore how promotions influence online grocery shopping.

We were convinced that those who regularly bought treats like crisps, cake and chocolate (treat shoppers) would receive lots of promotions for them: adverts, money off and multibuy offers. It seemed a no brainer: those who bought something were surely more likely to be encouraged to buy more on future shopping trips.

The reality

Frequent treat shoppers were more likely to be targeted for promotions. They just didn’t see them.

This group were using workarounds to skip through the shopping process. Things like pressing “repeat last week’s order” – then deleting what they didn’t need from their basket. Or just adding items from their “favourites”. Their shopping trips were short. Targeted promotions often didn’t reach them.

Conversely it was new shoppers building baskets from scratch who were exposed to far more promotions. Their shopping trips were taking 4-5x longer. They had much more time to be shown promotions.


Frequent online grocery shoppers just wanted to get their shop completed as quickly as possible.

One consequence was their baskets were very similar from week to week.

A lovely new study from a team at Cornell provides definitive proof on the topic. They explored 2 million shopping trips by US consumers using data from a representative shopper panel capturing both bricks and mortar and online shopping trips.

Analysis of the massive dataset revealed that when people shop for groceries online there is much less variety in their shopping baskets. What’s more, online baskets are more similar over time.

People buy from far more categories when they go to a real store.

Underlying needs

What this study confirms is that online grocery shopping amplifies inertia: people stick to buying the same things over and over. Most people are using the channel because it is easy, fast and convenient.

In store, you can’t help but be inspired by what you see, hear or smell. Whether it’s the purple-black hue of an aubergine, the marvellous marbling of the steaks or scent of fresh bread – this context is powerful. It influences what we buy more so than we realise or are willing to admit.

Closing the say-do gap

Observational research is the key to unlock complex research questions like this. You might have a strong hunch about what is going on – but if you skip to a solution you might miss the root cause.

The say-do gap means asking people to tell you what they normally do won’t cut it. People are often poor witnesses to their own behaviour, especially when it’s habitual.

Online you can let people get on with their habitual journeys, then get them to recap. In store you can let people browse and buy, then get them to talk you what they’ve just done.

And even if you a dataset with 2 million shopping you’ll still have outstanding questions. There’s no substitute for spending time with people to answer your list of ‘whys’.