The woman, who did not want to be named, says her 18-year-old son was helping her get her groceries through the self-service checkout at Countdown in central Dunedin when the incident happened, earlier today.
He didn't have any ID with him so a staff member told them they could not purchase the wine.
After her son left, she went back to the supermarket to get the wine and was shocked to find that, once again, they refused to let her purchase the alcoholic drink, even though her son was not with her.
"I was in to buy some low alcohol wine to put aside for Christmas, helping me was my 18-year-old son. While I was getting my club card and cash card out he helped me by starting to swipe the items across the self-service checkout," the woman recalled.
"As the wine went across the lady came and asked him for ID as he was the one buying it, I debated this and said he is my son (and had my card's in my hand). He unfortunately did not have his ID on him even though he is 18.
"What kind of a world is this where you cannot go to the supermarket and have your children help you? He has helped me many times in the past and it has not been an issue, even with wine and even at this supermarket."
The customer explained her son then left and she went back into the shop to purchase the wine.
"I was declined again! I asked if I could come back later and purchase it and the supervisor said she didn't know. What the actual? This interpretation of the liquor laws is absolutely ridiculous. I am very frustrated with what happened and actually humiliated," she added.
Social media users sympathised with the woman's experience and many shared similar incidents.
Countdown replied to the customer, saying the company has "many obligations within the community" and "one of these is for the responsible and legal sale of liquor and tobacco".
The company added that this is a measure in place to prevent "secondary supply" of alcohol.
"To help prevent 'secondary supply' of alcohol, our policy is to request identification for any person in a group where a member of the group looks under the age of 25 and our team reasonably believes there is a possibility that alcohol may be being purchased for this person. At times, we may need to refuse customers service in order to comply with this policy."
The customer pointed out that, while the policy makes sense to a degree, it also states that an exception can be made if they are the parent of the minor.
The woman says it was "very obvious" that they were mother and son.
"I get it about denying the first time, but to then deny me on my own was silly. Problem was I didn't try to hide, I suppose. How do we 'prove' kids are our children?"
Countdown has been approached for comment.
"We take our responsibility around selling alcohol really seriously because there are significant consequences if we get it wrong. Our policy is that where there's a person in a group who looks under 25 and our team has reason to believe that beer or wine is going to be supplied to a minor, we reserve the right to ask for ID or to refuse the sale," a spokesperson said.
"Our team has to make a lot of judgement calls every day and we're always trying to get the right balance between adhering to the law and making sure customers can safely access the products they want at our stores."
