For the most part, consumers have a game plan when they enter a store—they know what they intend to buy and stick closely to their shopping list. Still, in-store shopping has one advantage that online doesn't: the ability to see and feel items in person.  

That's likely why many people end up spending more then they intended to. 

A May 2018 survey conducted by AYTM Market Research for Blis asked 2,000 US internet users ages 18 and older whether they spent more than intended when shopping in-store. Roughly 22% of respondents said the spend about 10% to 20% more than they planned to when browsing in-store, while 14.9% said they spend about 20% to 40% more. 

Meanwhile, 10.2% said they actually spend about 50% more than they initially thought they would. 

What's most interesting, however, is that while 16.3% of respondents said they stick to their list, they end up purchasing items digitally after seeing them in-store. What might not have been an intended purchase when they entered a store became one once they saw it in person—even if the transaction occurred online. 

Despite online shopping's widespread appeal—we expect about 70% of the US population will make a purchase digitally this year—what occurs offline matters, too.

According to a Murphy Research survey conducted in January 2018, 69% of US internet users made an in-store purchase in a typical month.