The multiples risked damaging the PBA category in the same way they had the standard ale, canned lager and cider categories through promotional prices such as 24 for £16, the brewery claimed.
One major retailer had already begun to offer ale at "an unsustainable" £1 per bottle, complained Marston's take-home category manager Justin Way, who said that he expected other retailers to follow suit.
"The premium bottled ale sector simply doesn't need these kind of bargain-buy promotions in order to drive sales. It's performing well as a category, with sales up 4.7% to £180m to the end of April this year [Nielsen]," he said
"Despite the tough times, plenty of loyal consumers are willing to pay premium prices such as £2.50 per bottle for brands such as Pedigree and Hobgoblin."
Marston's was not just calling for action to protect its own brands, said Way.
"We are optimistic our competitors in the PBA category will have the same take on this as us. This isn't just a brand agenda — we want to see the whole category grow in value."
The beer and cider buyer for a national high-street chain agreed that employing similar promotional tactics to those used to shift lager and cider was bound to impact premium ale's value. "Traditional retailers are about 90% reliant on lager rather than ale sales within the beer market," he said.
"Some grocers are trying to bridge this gap by offering deals on PBA, but clearly the brewers have a margin to protect and are unlikely to encourage them. If retailers begin to mirror the multipack buys seen on lager, ale suppliers simply won't be able to maintain the price they are used to."
Marston's spoke out following the release of the first Premium Bottled Ale Report this week.
The report is an annual sales and trends analysis of the premium bottled ale sector based on Nielsen and TNS data and commissioned by Marston's.