Questionable advertising on store exterior

We went to do some evening shopping and saw this shop’s advertising. From a distance it said 80% off everything storewide. Then we saw above the door that there was on brown paper the additional text Take an EXTRA 20% off.

It was only when standing right in front of the signage did the tiny writing on the black background become visible, saying Up to. I wonder how many people are have been lured in by the “80% off storewide” without noticing the miniscule “Up to”?

By saying Storewide this mean that everything in the store has a discount of some size (possibly very small) discount. But how do you work out the final discount?

Here are two ways that it could be worked out:
For a product with an 80% discount, is the additional 20% off the original price (20% of 100% added onto the 80%), which would make it free; or was it 20% of the remaining 20% (which is 4% of the original price), so you would get an 84% discount? Clearly the former is unlikely, so it has to be the latter.

Let us assume that some product has a 5% initial discount. Does this then become a 25% discount (5% plus 20%); or does it become 20% of 95% ((100%-5%)x20%) which is 19% to add on to the initial 5%, so a final 24% discount? Based on the maximum 80% discount discussed above the former is unlikely. I suspect that the average punter off the street would, without thinking, expect to get the 5%+20%=25% discount.

Final example: if the initial discount is 50%, would the average punter expect to get 70% (50+20)%, or (50%+(50*20)%)=60%?

The signage is verging on deceptive, and the discounting is contentious.


I had a similar experience at a McLaren Vale winery recently. They had a tasting fee refundable on minimum of 2 bottles purchase. Say a case of wine has a 10% discount on $500 and the tasting fee is $20.

A reasonable person would expect $500 (wine) -$50 (discount) - $20 (refund) = $430. The winery did $500 (wine) - $20 (refund) - $48 (discount) = $432. Not a huge difference and I empathise with their business challenges in recent years but I did not take it well because there was either a partial refund of the tasting fee, not a full one as advertised, or the discount was less than 10% again not as advertised.

The lovely counter staff indicated I was not the first to complain; the manager/owner would not budge. I cancelled my $500 purchase and bought the minimum required to recoup my tasting fee.