I doubt that anyone shops around for the cheapest mints. But perhaps we should, given my discovery that WH Smith are overcharging on an extraordinary scale.

I can pick up a packet of Trebor Soft Mints for around 44p in the newsagents at Canary Wharf – hardly a bargain basement venue. But WH Smith charge an eye-watering 57p – more than 25% more. And they wonder why they’re in long-term decline!