Two for one! 20% off! Reduced to clear! Promotions scream for our attention. They're designed to get us to look at the products that brands and supermarkets want us to buy. And those aren't always the cheapest or the best.
Academic studies have found human psychology and behavioural biases cause us to buy goods on sale because we assume we're getting a bargain. Marketing gurus know this; it's their job to take advantage of our desire for a sale.
One of the most common marketing tricks you'll see in a supermarket is the placement of key (expensive) products at eye level. The products that make the largest profit margin will usually be at eye level and the items most attractive to children are placed where they can best see them. Marketers also use colours like red and bright orange to draw our eyes to "special" promotions.
There are plenty of examples of supermarkets using promotions tactics but not delivering a better deal. Some of the "best of the worst" examples consumer advocacy group CHOICE has seen recently include a clearance sale of hair dye – "Was $18.49, now $18.49!" – and sauces selling for 99c each but on sale at "three for $6"!
There is one simple way to save on your weekly shop. Look past the promotions and find the unit price to really compare the cost of products.
The unit price is usually displayed underneath a sale price and it states how much you pay, for example, per 100 grams of each product. By helping you compare prices easily, unit pricing can save you hundreds of dollars off your grocery bill each year.
For example, if you're shopping for quick oats for a winter breakfast, you're faced with dozens of choices from different brands that sell in vastly different quantities, from bulk products to single-sachet serves. A quick glance at the unit price of quick oats will let you find the product that costs only 15 cents per 100 grams, significantly cheaper than the $4.52 per 100 gram individual sachets of oats!
Unit pricing helps consumers cut through the marketing to find the best price but it isn't perfect. It currently only has to be displayed in large supermarkets and not small supermarkets, hardware stores or chemists.
Of course, price isn't the only consideration in the supermarket. Quality and, increasingly, ethical concerns, determine what makes it into our trolley. Consumers can't always trust food labels to navigate these decisions.
Whether it's "oregano" that is actually made with 50% sumac leaves or "free range eggs" that come from chickens that don't go outside, there are dozens of labelling lies in every store.
The supermarket is a minefield. At least unit pricing can help you cut through the marketing spin and find the cheapest price.
This article was originally published by The Age on 13 April 2016. It represents the views of the author only and does not necessarily reflect the views of AMP.
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