Singapore Airlines' budget offshoot Scoot has become the second Asian airline to introduce a child-free zone.
The airline has announced a separate "Scoot in silence" cabin behind business class with more leg room than standard economy where children under 12 are banned.
Scoot CEO Campbell Wilson said there were still lots of other options available.
"No offence to our young guests, or those travelling with them, you still have the rest of the aircraft to choose from."
Launched in June last year, Scoot operates daily services to Sydney and five flights a week to the Gold Coast from Singapore. The airline is in preliminary talks to join forces with Tigerair Australia.
Scoot's announcement follows that of rival, Asian budget carrier AirAsia X's, which introduced a similar "quiet zone" on its aircraft in February this year where children under 12 are banned.
AirAsia's fellow Malyasian carrier, Malaysia Airlines, has long banned infants from travelling in first class on its planes after complaints from big-spending passengers who were unable to sleep due to crying babies.
Traveller's family holiday columnist Tracey Spicer says the concept of child-free areas on planes is "offensive".
"It's something I feel very strongly about, it's treating children like they're animals in a zoo," she said.
"And it treats families like they are second-class citizens. You end up with all the families shoved down the back. It will make every flight a nightmare for families."
Tolerance is the key to happy air travel, she says, not corrals.
"Some of the worst flights I've had have been because of adults, not children. Those who had drunk too much, or were smelly, or too big to fit into their seat.
"It is discrimination. Where does it end?"
However, AirAsia X says it has not received any negative feedback since introducing its child-free zones.
The airline's international head of marketing, Stuart Myerscough, said guest feedback had been "overwhelmingly positive".
"We have not received any negative feedback. In fact, the service is always heavily booked and we consider it to be an overwhelming success and one of our most popular innovations yet," he said.
But while low cost airlines claim they are offering their passengers a popular extra with adults-only sections, they are also using the option as a way of extracting additional revenue.
Both Scoot and AirAsia X passengers have to pay a premium to be seated in the child-free zones.