This age-old debate … there is nothing new under the sun …
Here is the legal answer that is likely to be applied in most jurisdictions within the USA. (and, as with many “answers” in law, you’ll quickly see there is no set-in-stone to-be-applied-everywhere, all the time, answer)
We go to the Uniform Commercial Code for guidance on this issue.
UCC section 2-314: Implied Warranty of Merchantability:
(1) Unless excluded or modified (Section [2-316]), a warranty that the goods shall be merchantable is implied in a contract for their sale if the seller is a merchant with respect to goods of that kind. Under this section the serving for value of food or drink to be consumed either on the premises or elsewhere is a sale.
(2) Goods to be merchantable must be at least such as
(a) pass without objection in the trade under the contract description; and
(b) in the case of fungible goods, are of fair average quality within the description; and
(c) are fit for the ordinary purposes for which such goods are used; and
(d) run, within the variations permitted by the agreement, of even kind, quality and quantity within each unit and among all units involved; and
(e) are adequately contained, packaged, and labeled as the agreement may require; and
(f) conform to the promise or affirmations of fact made on the container or label if any.
UCC section 2-316: Exclusion or Modification of Warranties:…
(2)Subject to subsection (3), to exclude or modify the implied warranty of merchantability or any part of it the language must mention merchantability and in case of a writing must be conspicuous,…
(3)Notwithstanding subsection (2)
(a) unless the circumstances indicate otherwise, all implied warranties are excluded by expressions like “as is”, “with all faults” or other language which in common understanding calls the buyer’s attention to the exclusion of warranties and makes plain that there is no implied warranty; and
(b) when the buyer before entering into the contract has examined the goods or the sample or model as fully as he desired or has refused to examine the goods there is no implied warranty with regard to defects which an examination ought in the circumstances to have revealed to him; and
(c) an implied warranty can also be excluded or modified by course of dealing or course of performance or usage of trade.
To put it simply, retailers (“merchants”) may be liable for breaching the implied warranty of merchantability when they sell a defective product and there was no legally-valid exclusion of the implied warranty. Exclusion of warranties is addressed by UCC section 2-316.
These cases are extremely fact-specific, and there are often reasonable arguments on each side. Whether a wine retailer is liable for breach of implied warranty of merchantability is certainly one of those cases where there are reasonable arguments on both sides. The buyer will point to UCC section 2-314, and the seller will defend themselves by pointing to UCC section 2-316.
Fun stuff.