Most shops I frequent are too small to do unit pricing (under the law) and don’t do it voluntarily, but it is disclosed in their multi store / area wide specials catalogue. I would love to see it in little supermarkets, can’t be too hard to do, particularly for sales as their specials data comes from HQ and they print the tickets. Have seen same product as per 100g and 100ml or each. Tea bags were priced as 4cents each and $24/kg, tinned tomato as $1/100ml and $10/1kg.
My gripe with Specials tags is they are sometimes under the wrong product - I now check the last few digits of the bar code against the product. I have been caught with Specials on a product eg Drumstick $4.99, tag not specifying any or all flavours, to find it only applied to a few and not disclosing this till the checkout. Also Old tags - left from last campaign - where you end up paying full price again, and missing ‘regular price’ tags. Fresh fruit & veg is a big problem with only about half with any price. My assumption, which seems to be backed up by experience, is that - no price = very dear.
Another gripe - sweet corn, now only comes pre-packaged with the tops & bottoms lopped off & most husk removed, wasting about a third of the edible part. Unit price is cheaper than whole cob. I prefer to buy whole cobs and use the husks in compost, while I wait for my own corn to mature. I know what we get paid for produce and am astounded at the supermarket prices. I don’t have Aldi, Coles, Woollies or variants here.