Pint of Guinness index

[Leo]

I struggle to believe that Weatherspoons are commanding significant discounts from Guinness in Ireland, based on their sales in the UK.

I doubt they are negotiating separate deals, their model is to skip intermediaries and agree long term contracts, and beer isn't the only product pubs require. They eliminated all Heineken products a few years back after negotiating a 20 year deal directly with Budweiser.