You have been enjoying the chocolates that you received for your birthday/were given by an admirer/bought for yourself, but they are going fast. Holes are appearing in the crinkly plastic tray. Round holes. Square holes. Triangles. Diamonds. Ovals. You have nearly finished them off.
But, oh sweet and gorgeous but...
You remove the plastic tray and, lo and behold, there is another identical layer of chocolates underneath. Double the fun. Applies equally as well to tins of biscuits.
Whoever originally had the idea of putting two layers into chocolate and biscuit boxes should be knighted. Canonised even. Let's raise a mug of tea and toast them, whoever they are.