Walkers Max are promoting their grab bags with a 2-for-£1 flash in corner shops, and I wonder how many retailers have done the maths? My local Best-One is selling these singly at 55p, and if he is buying from Bestway he is making a 16p net margin on every bag he sells.

However, if he sells two bags together, he makes a net margin of 23p – and his profit on return has fallen from 34% to 27.4%.

On the Booker website it lists both the pricemarked 2-for-£1 and the standard 50g products. The recommended retail price for the promotional packs is 57p and for the standard pack is 54p. In the absence of any commentary about possible overriders that are available to local retailers, it does not seem to make much sense to take part in this promotion. Perhaps someone could let me know how it could?