One of the things that often came up was how large packets were more expensive than the small packs, often claiming the larger pack was great value. Spreads were shown as an example and this can be found at my local Co-op a large 1 kg pack of Clover cost £3.99 and two smaller 500g packs can be purchased for £3.00.
Some of the 1kg packs are marked value large pack and the others value family pack. The pack marked Large Value Pack has been produced in a container carefully designed it looks bigger than the family pack.
The said many shoppers don't have time to check out things whilst shopping, I wonder if supermarkets rely on this.