8. You'll walk the store the way they want you to

There’s nothing haphazard about the layout of your grocery store. Sure, some of it is practical (like refrigerated cases along the periphery or meat cases in the back by the store’s loading dock), but some is carefully calculated to help you part with more money. Walk in the front doors and chances are you’re faced immediately with hard-to-resist items (not on your list) like fresh-cut flowers or just-baked loaves of bread. Just try walking past them en route to a carton of milk without tossing something extra into your cart. In fact, research has shown that 60 percent to 70 percent of what ends up in our carts is unplanned.