When you go shopping in a supermarket, and fall upon those “two for the price of one” offers, I’m sure you are delighted at the bounty of Tesco et al. But think again.
Big supermarkets are appalling for suppliers to deal with, and due to their purchasing power, there are very few other markets. Read more in the Guardian. This is one of the reasons I try not to use supermarkets, although it becomes increasingly difficult.
[edited to add] The comments are pretty bloody depressing too.