the under cover economist

I have just read "the under cover economist" by Tim Harford. This book is about the economics of everyday living. It deals a lot with the price of coffee, an important issue if you spend your life in dire need of hot caffeine fuel. He made some good points about the price of goods in a supermarket. He claimed that the price of basic things at a fancy supermarket (Marks and Spencer or Waitrose) were pretty similar to those in a more basic supermarket such as Morrisons. However, in Waitrose the basic food is hidden by the more expensive stuff (freshly squeezed mango juice e.c.t.). This example was used to illustrate the idea of "scarcity".