Posted yesterday, the video has amassed more than 17,000 views and users commented in support of the cheeky bathroom tip.
"I'm always using the first class bathroom," one user wrote.
"I totally thought we couldn't use the first-class bathroom," another added.
Kamalani's third piece of advice was to never accept an airline's first offer when they attempt to buy you off an oversold flight. Instead, she said, always negotiate additional money or perks.
The question of bathroom us is an old one and has become more than a little heated online in the past.
In 2019, one disgruntled Australian business class passenger took to a community thread (under the username Gjspectre), to complain of the 'increasing number' of economy passengers using the business class toilet.
"On my last flight to Adelaide a clearly drunk passenger did this three times, with absolutely no resistance from the crew," he wrote.
"I'm not particularly fussed [but] perhaps their announcement at the start isn't enough? I've commented before that Virgin Australia with their white rope deters this effectively."
Users seemed to agree with Gjspectre, with one fellow user writing: "Get them back where they paid for I say. Qantas doesn't have single class service aircraft. They charge extra for convenience and people pay for it with points and/or money."
Another said it was something staff could "easily address" by telling instructing economy passengers to go down the back.
Over on a Quora thread, people had a similar perspective; keeping the divide was only fair, especially if first-class bathrooms had additional luxuries like showers and toiletry products.
According to Fobes, the line may not be so black and white. In 2019, they reported that, for domestic flights, "first class bathrooms are for all passengers (mostly)."
Representatives at American Airlines, JetBlue and United told Forbes there were no lavatory class restrictions on US domestic flights.
Alaska Airlines and Delta were reportedly stricter and said guests should use the lavatory in the cabin they were seated in unless the crew instructed otherwise.
Encouraging passengers to use the mid or rear lavatories isn't just a matter of paid privilege either.
It also reduces the likelihood of people congregating in groups near the cockpit door and disrupting food and beverage services which usually begin at the front of the plane.
Whether or not Kamali's trick actually works, however, is a question of the airline you fly and the leniency of the crew.
Those flying with Air New Zealand are out of luck unless there is a good reason.
"Generally our Economy and Business Premiere areas are kept separate, including the bathrooms," said an Air New Zealand spokesperson.
However, they added, there could be exceptions depending on circumstances, such as passengers requiring wheelchair access or a toddler waiting in a long queue for an economy toilet.
