• by Sarah Mahoney  @mahoney_sarah, May 9, 2012

While consumers are spending less time in grocery stores, and more time researching purchases before putting their lists together, impulse buying is alive and well: A new study from the Point of Purchase Advertising International reveals that 76% of all grocery purchasing decisions are being made in stores. That represents an all-time high, the trade group says. 

What’s more, the study, which added EEG and eye-tracking technology to attitudinal findings and consumer interviews, found that when shoppers engaged with an in-store display and touched a product, 66% of those grabs resulted in a purchase. And overall, shoppers are still lousy at projecting how much they will spend, with the average person misjudging the amount by 35%, either high or low.

The study reports that 24% of purchases are specifically planned before the consumer starts wheeling the grocery cart. The rest of the shopping decisions fall into generally planned purchases, substitutes, or unplanned buys. Even when accounting for those impulse buys, the trade group says, 57% of shoppers still spend more than they planned. 

And while unplanned purchases, naturally, drive spending up, the surprise was by how much: Those who overspend on impulse items typically do so by 200%.

Plastic leads to even greater sloppiness. Those shopping with either a debit or credit card are even less accurate in their calculations, buying larger quantities of goods and making more unplanned purchases than those paying cash.

Overall, one in six of the observed purchases were made when a display with that brand is present in store, with toaster pastries, pickles/relish, dishwashing soap, and pet supplies getting the biggest boost.

POPAI says the data, based on 2,400 shoppers in four broad geographic regions, suggests that in-store displays work best when aimed at a “core group of loyal, female stock-up shoppers” -- even those who are more likely to plan purchases before shopping, using lists and circulars.