If Christmas shopping in crowded, overheated malls makes you cranky and uncomfortable, there may be a very good reason for that. According to the New York Times, evidence suggests that the less comfortable you are during the holiday shopping spree, the more money you’ll spend.

So stores crank up music, repeat the same songs, over and over again, pipe in smells, and confuse us with complicated offers. All of which makes it more likely we’ll part more readily with more money.

Music played at high volumes, for instance, is irritating, and that’s why we campaign against it here at Zoomer Media. But researchers from Penn State and the National University of Singapore concluded it was one of several factors that leads to overstimulation and “a momentary loss of self-control, thus enhancing the likelihood of impulse purchase.”

Customer inconvenience can apparently also work to retailers’ advantage. We know that staples like bread and milk are often at opposite ends of the supermarket, making shoppers cross the length of the store, past shelves of tempting goodies. Designers use the same logic in department and specialty stores. And they figure, if we’re irritated by the loud music, bright lights and crush of the crowd, we’ll see there’s a simple way out. Just buy the expensive gadget or whatever you’re looking at and be done with it.

And that will lead to even more buying, according to the theory of “shopping momentum.” Because after fretting about the first purchase, buying the net things gets much easier..