The reaction was instant and certainly wasn't about sandwich alternatives.
Mum Maddie wanted some suggestions for alternatives to sandwiches that she could make for her husband's lunch.
Aside from being a "1950s housewife," Maddie was called "weird," and a "slave".
"Our advice is to stop making his lunches," wrote one.
"My husband can make his own damn lunch," said another.
"I was married for twenty years and my favourite packed lunch for my husband was called a Get it Yourself with a side order of I'm not your mother," chimed in one member.
It's likely some of the people who got back in touch with Maddie were breaking one of the four rules of North Shore Mums club: "Be nice. Treat people as you could in the real world."
Maddie replied that the nastiest comments, which the administrators deleted, had "devastated" her.
She said her husband worked an, "extremely physically demanding job," cooks every other night and does housework.
"The least I can do is make him a bloody sandwich."
It's not the first time the vexed issue of who makes the sangas in the relationship has been raised.
Earlier this year, on Stay at Home Mums, a blog and Facebook group, the issue also came up but the poster recognised from the get go it was a charged subject.
"I get criticised because I pack my hubby's lunches. He works full time and goes to uni so that I can stay at home with our children so it's the least I can do for him."
Like on North Shore Mums, a number of people questioned why the bloke couldn't make his own food.
"No way! He has two perfectly good hands and can make it himself!" wrote one.
"My job is 24/7 and I don't feel that making your own lunch is a big deal. If I was going to work outside the house I wouldn't expect him to make my lunch!" said another.
One poster said her husband was "responsible for himself".
However, others came to the poster's defence.
"There is nothing wrong with anything you do for your husband as long as it's what you want to do and not because you feel you have to".
The North Shore Mums group has stirred up controversy before.
In 2016, one mum got so exasperated with North Shore Mums she set up rival blog called 'F*** you North Shore Mums'.
Mum of two Mel accused the administrators of being quick to censor and said they were "fun police" for deleting what she believed were witty posts.
On her blog, Mel said she "grew tired of the mundane posts about Fiji, reasonably priced cleaners, lunch box ideas and posts by people making their first fondant cake and fishing for compliments.
"Even the 'popcorn' posts like circumcision, parking with prams and anti vax parents - which would make for thrilling viewing - would get deleted just before they got good."
She said the page had all the excitement of a "sock full of s***".
She changed her Facebook name to 'Far Kew' (Geddit??!) and began posting funny, and deliberately provocative, posts on the group's page.
However, she didn't last long. What she calls the "ninja admin" deleted her posts as well as her posting rights.
News.com.au has contacted the administrator of North Shore Mums to ask if they reached out to Maddie and if some of the stronger comments broke the group's rule of "Be nice".
