It's a cat and mouse game.
Just as many shoppers are trying to stick to a budget, retailers are actually studying ways to get them to spend more.
"There is a whole science behind it," Nick Jones of advertising agency Leo Burnett. "We look at everything from how people shop, the store patterns they follow through the store and where their eyes go."
This new shopper marketing is a $35 billion dollar business that’s doubled in the last five years, according to Jones.
Some retailers are trying brain scans while others are secretly video-taping your every move to see exactly what triggers you to spend.
And shoppers feel it.
"They get us to spend more money and buy stuff that we don’t need," said shopper Ramesh Narayanam.
Experts warn: get used to it. A new book called "Brandwashed" by marketing guru Martin Lindstrom reveals several tricks companies use to manipulate and persuade.
Ever notice why shopping carts have doubled in size over the years? Studies show the bigger basket means shoppers will buy up 37 percent more. Those kiddie carts, Lindstrom writes, will get you spending 25% more.
Why is the milk always in the back of the store? The hope is that on those quick trips, you still might stop and buy more along the way.
John Greening of Northwestern University’s Medill School of Journalism knows the book and its claims. He's a marketing wizard himself behind Budweiser’s "Wazzup" campaign.
"Let the buyer beware," says Greening. "If you are against it it’s manipulation, if you are for it, it’s a service."
Greening said it often comes down to getting you to buy things you didn’t even know you wanted.
He points to why some sale items are displayed in the front of the store. At the end you think about how much you are spending, but at the beginning you are lured by the deal and haven’t even gotten to the things you need.
"This encourages you to buy things that are not on your list," he said.
Shoppers say it’s work not to "buy" into it.
"I stick to what my plan is," says Kim Lloyd. "In that way I shop like a man."
But Greening said like they used to say in the beer business, it’s all about "personal responsibility," and no one wants to talk about that.