Asda has been selling 24 bottles of 300ml Budweiser for £11 on Rollback since 28 September. Williams said his £1bn-plus buying group could only purchase the same pack size direct from AB InBev for closer to £17 over 50% more and predicted wholesale customers would stock up at the supermarket instead of their usual cash & carry.
"Twenty-four bottles is a full-blown wholesale case," he said, warning that it was "inevitable" independents and pub operators would buy the product from Asda.
The deal marked a worrying change in promotional tactics at the mults, which had previously focused on 12 or 15-pack multi-buys, he added. It also flew in the face of the sensible drinking push. "In this day and age of responsible consumption and retailing, offering a major brand for under 50p a bottle completely contradicts all the messages that retailers and wholesalers are giving out."
Last week, AB InBev said rising raw material and energy costs meant it would have to pass on a 7.8% price increase across its UK portfolio from 2 January to maintain its businesses on a sustainable footing. "At a time when prices are going up in the market and brewers are putting up prices, to retail at that sort of price is crazy," Williams added.
An Asda spokeswoman insisted: "We're as committed to our role as a responsible alcohol retailer as we are to providing affordable deals for our customers."
AB InBev declined to comment.