Sorry, millennials, but a 25-year-old should be able to buy food.

A room full of pregnant women, overwhelmed by the size of their ballooning bellies and the enormous change that is about to sideswipe their lives.

“Do you know,” the midwife leading the prenatal class asks her 10 couples, brightly, “the average age that an Australian child now leaves home?”

Nooooo, we don’t know, wise one. Please, share.

“Twenty-eight years old,” she tells us, with a wicked smile. “This little person living inside you is going to be under your roof for an average of 28 years.”

For some of us, that information was more shocking than what followed, a birthing video where a woman howled like a dog in a paddling pool full of goo.

I thought of that moment last night when I saw a young woman called Erin walking around a supermarket on a reality show called Married At First Sight, flummoxed by the physical characteristics of basil and pondering the possibility of buying a single celery stick.

You see, Erin had never been food-shopping without her mother. And Erin is 25.

Listen to the hosts of The Binge on all that is wrong with Married At First Sight, here:

The differences between Generation X and Generation Y is a tired, tired conversation.

Since the dawn of time, Old People have thought that Young People are silly and feckless, and Young People think that Old People are dumb and patronising. It’s the natural order of things.

But as an Old Person who works the middle of a delightful, sweet-smelling, extremely camera-happy muddle of Young People, I think their inability to leave home could be a genuine generational difference worthy of note.

Generation X could not WAIT to get out of the parental nest, earn their own money and embrace living in a succession of crappy shared houses where they would perfect the art of nagging their slacker housemates to change the bong water every once in a while.

Generation Y wonder why the hell they would subject themselves to anything less than mum and dad’s place, where there’s “free” wifi, a screening device in every room and a pile of clean washing that magically replenishes itself every couple of days.

The end result is Erin, who has to call her mother to find out what the difference is between salted and unsalted butter. Erin, there’s a clue in the title.

Erin didn’t seem to have much luck when it came to the food preparation, either. Post continues after video…

Twenty-five is not young. At 25, a person should have had to fend for themselves. They should not be standing in the middle of a supermarket, paralysed by their inability to open one of those infuriating plastic bags for grapes.

Yes, it’s tough. Almost as tough as deciding whether you want lite, soy, almond or A2 at the milk fridge. But you can do it, Erin. You really should have done it by now.

The thing that I want to yell at the cossetted Young People is that independence cannot be overrated. The freedom of your first pay packet, the joy of the four (probably thin, probably dirty) walls in the first home on which you pay the rent, that is empowering stuff.

In my first proper job, living in a city hours from my hometown, my best friend and I used to walk home from the train to the place we shared with four other people and pinch ourselves – WE LIVE HERE, WE HAVE JOBS, WE ARE GROWN-UPS. Being a grown-up was something to run towards, not away from. It didn’t mean mortgage-marriage-babies. It meant freedom. And buying whatever the hell you wanted at the supermarket.

I know, I know, things are different now. Education is expensive. Rents are high. Parents are cool, yo. They don’t mind if you stay out all night and bring home two special friends for breakfast.

But is this ever-extending umbilical cord as bad for parents as it is for the supermarketly-challenged kidults?

Having a child is a lifelong commitment, but shopping for them, cooking, cleaning, driving them around, paying for their every whim. There has to be an END to that, right? Yes, it's called adulthood.

Erin, living with your parents and having them buy every piece of food that enters your mouth, that's not the easy option, it's actually the tougher choice. Because one day, you will have to find out who you are.

You might think that you know the answer to that right now - you're a person prepared to marry a stranger on a television show - but you don't. You don't know who you are until you choose your own life.

And your own shopping.

I hate to break it to you, Erin, but there are eight types of Weetbix over in Cereal, and you might just have to cut your losses when it comes retrieving the $2 from the trolley slot.

But you'll be right.

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