The 560g jar of Vegemite costs AU$19 at Sydney airport, twice the price of the same jar bought off of any high street.
Social media users were horrified by the crazy mark-up.
"The infamous 'your fault for not ducking up to the shops before your flight' tax," one person wrote.
"Probably be cheaper to get a taxi to Wolli Creek (near the airport) Woolies, buy your Vegemite there, then get another taxi back to T1." another said.
Other people were less concerned about the price of the Vegemite and instead were wondering why anyone needed to take it on a flight in the first place.
"Those here who travel with Vegemite … why? Is it you don't want to try something new, or? I just seriously don't get it," one person wrote.
It's no secret prices get bumped up a bit at the airport but generally the changes are subtle enough that people accept they are going to pay a few dollars extra for their morning croissant or a schooner of beer.
Last year, a social media user posted a photo to Instagram of a bottle of water retailing for $9.17.
Although you won't have to fork out $9 for a bottle of water at every shop in the airport, be prepared to pay at least $4 for a bottle of Mt Franklin. You can get the same bottle from a supermarket for $2.15.
When it comes to grabbing something with a little more kick, in Sydney's CBD the average price of a schooner of beer is around $8, but in Sydney Airport a beer costs anywhere from $9.50 to $12.50.
News.com.au has contacted Sydney Airport for comment.