Anticipating that the customer acts rationally why would they pay more for a good from a limited stock when the purchase can be made more easily, from a wider choice at lower cost? Many of us decry the death of the high street but unless the game changes then expect to see more retailers exit in the next years.
Perhaps Superdrug have got it right - I got my Mouthwash there today on a buy one get two free deal- don't know if this has an equivalent term to the usual BOGOF.
Number 35 Common Sense
Common Sense is (of course problematic) it is something that needs to be considered with Epistemology. We can see that Common Sense has been an issue for Philosophers for many years (from Aristotle onwards) and it is important that Philosophy tackles questions rigorously rather than blindly accepting the current beliefs, as Crofton points out the ideas that the world is flat and that the sun rotates the earth were seen as common sense by many educated people for hundreds of years.
Here's the Lord Bragg 'In Our time' on the Subject of Common Sense (great stuff) guests include Anthony Grayling.