Superstores have developed sophisticated tactics to turn 'grazers' into spenders. Serena Mackesy scents a conspiracy in the mall
For the past week, thousands of eager New Yorkers have been pouring in to a new retail shrine in the heart of their city. Nike, purveyor of footwear to the gullible teen, has opened a new NikeTown store in Manhattan - this following the success of the original "Town" in Chicago, which has an annual gate of 3.5 million people. In this temple to the well-supported arch, visitors watch vast screens replaying heroic deeds, ooh and aah at a collection of Michael Jordan's trainers and strain to touch the gold track shoes worn by sprinter Michael Johnson in Atlanta. Nike's profits are booming.

Meanwhile in Britain, Kwik Save, the "pile 'em high, sell 'em cheap" chain - its stores the antithesis of the Nike experience - announced the closure last week of 100 of its low-luxury outlets. As rival supermarkets Sainsbury's, Asda and Tesco's refurbish, the punters return to them in droves. This, then, is shopping in the Nineties: if you can afford to be a customer, of a Nike or of a Kwik Save, you expect to be cosseted; if you aren't, you go somewhere else.

Time was when shops just sold things. Now the luring and keeping hold of potential customers has been elevated to a science, and one that retailers in Britain and the US need doctorates in if they are to survive.

The American guru of retail layout is one Paco Underhill. He knows that the critical point in flogging goods is drawing attention to them. Because while we may think we're free spirits with free will, the human psyche is prone to a number of predictable reflex actions. Chances are you've noticed that little black number in the far right-hand corner because it's been placed there just for you.

Last week's New Yorker magazine dedicated nine pages to a profile of Underhill and the discipline he calls "retail anthropology". His company, Envirosell, has advised firms such as Levi Strauss, Starbucks, McDonald's, Blockbuster and Apple for the past 15 years, and has amassed more than 100,000 hours of film of shoppers on the move which provide empirical proof of our animal tendencies.

The Invariant Right, for instance. Did you know that all shoppers, anywhere, turn 45 degrees to the right when they enter a retail space? Or that when walking people follow roughly the same rules as on the road - Americans to the right and the British to the left? Or that it takes between five and 15 paces after entering a shop for the shopper to actually take in anything around them? Underhill calls this the "Decompression Zone" and advises retailers to avoid putting anything of value here. Customer awareness of objects increases by 30 per cent as they leave this zone.

If retailers can get us to touch or interact with an object, their chances of selling increase incrementally: not for nothing do Gap and Benetton have piles of stroky woollens laid out on tables and shelves. Fondling, or "petting" as Underhill calls it, builds a relationship between fondler and fondlee. And once the relationship's there, we're more likely to take it home.

There's more.

Men and women, as we all know, shop differently. A man in America will spend nine minutes 39 seconds in a shop, a woman 12 minutes 57 seconds. That time gap has caused friction in countless relationships, but the retailer knows this: women buy more.

Men, still tyros of consumption, have infantile habits: as supermarkets sell more sweets by putting them at child level, so clothes stores sell more men's socks by putting them near the cash register, more ties by placing them by the shirts. If you're selling to both sexes, the boys' stuff sells best nearer the door: men, apparently, get uncomfortable brushing past women's clothes. What bothers women most is the "butt brush". A woman who is touched from behind while looking at a piece of clothing can be virtually guaranteed to put it back and move away. Thousands of years of having men on our backs has had its effect.

You can't just pull the punters in these days: you must keep them there as well. Margaret Harwood, communications manager of Capital Shopping Centres - which manages, among others, the Gateshead Metro Centre, the Potteries in Stoke on Trent and Lakeside at Thurrock, Essex - knows that promotions make a difference to the flow of people through her centres: "They lengthen the amount of time they're there. And the longer you're there the more you spend." Twenty-two million people a year pass through Thurrock, spending an average of three hours. Not bad compared with the 66-minute average in the United States.

Old techniques, like that in-store bakery smell, work less well these days as consumers become more hip to retail devices. Layout is more of a focal point.

"The grocers have all decided to put the fresh fruit and vegetables at the first inflow into the store," says Richard Perks, of specialist retail analysts, Verdict Research. "It gives a good impression of quality. It raises expectations". And it introduces petting into the decompression zone. You can fondle a peach or a tomato: the same can't be said for a frozen chicken.

This is all fantastic fodder for the conspiracy theorist. Once your eyes are opened, details assail the eye at every turn. Ikea, European masters of the psychological store layout, opened its newest outlet at Thurrock, Essex, last Thursday. Margaret Harwood is full of slightly ironic admiration for its techniques: "They get you through the whole store before you find you can't get out until the end." Having been affected at a vulnerable age by George Romero's classic zombies-in-shopping-mall horror-flick, Dawn of the Dead, I'm quite nervous in these Meccas to consumerism. Ikea was, to say the least, a bit nightmarish.

It wasn't just the Disneyesque layout - section entrances to the right, exits to the left, the promise of exit held tantalisingly before you - it was the way people were behaving. Watch a crowd and they become alarmingly robotic. Not a cupboard door remained unopened, a drawer unslid, a metal candlestick unstroked. Cassette holders held single cassettes for punters to pull out and slot back in again. The floor of the children's section was painted with hopscotch squares: respectable middle-aged women handed their bags to their companions, did a skippety-jump and headed, smiling, straight for the strategically placed dump bins of extra yellow shoulder sacks.

In the gently lit environs of the surrounding Lakeside Shopping Centre, the atmosphere was less apocalyptic, but the predictability factor remained the same. Despite the fact that the escalators deposited on the left, a good 75 per cent of those riding them turned right, waiting for gaps rather than alter course, as they got off. Lakeside doesn't, as do many American malls, have any particular features to slow down walking pace - which widens your peripheral vision - but, as Margaret Harwood says, "In America the malls tend to be a lot emptier; the pedestrian flows here are much greater because there aren't so many shopping centres". Traffic had a dual-carriageway effect: browsers in the left-hand lanes, walkers in the middle ones. They crossed the flow for one thing only: cafes and burger joints. Food, it seems, overrides the herd instinct.

Clothes shops sharkily have their racks organised in chevrons, pointing inwards: getting to the back is easy, getting out again, while avoiding knocking everything flying, takes time. Bins of hats and gloves emptied as cash-till queues inched forward. Men hung back behind their womenfolk at entrances, then drifted in, sheepishly, to feel up a piece of velveteen or a mohair crop top.

This is all great, but it makes you wonder. As marketing techniques become more sophisticated, consumers usually caught up, getting wise to the fact that supermarkets put the Coco Pops at six-year-old eye level. As fast as research companies categorise shopping personality types - "organised", "grazer", "decisive," "fulfilled" - so do they proliferate: executive- organised-browser; new-age fulfilled shotgun; trolley bandit. There have been signs, of late, of abreaction to advertising: Ikea's "chuck out that chintz" hasn't been an unqualified success, and those huggy "best a man can get" ads have turned a healthy number of men away from shaving with Gillette. What will happen when we realise we're producing Pavlovian saliva to retail order? Will the shopping trend of the 21st century be the jumble sale?