My family and I were passengers on that flight and were seated immediately behind him in the 4th. row. While I have a current dispute with Jetstar in relation to additional charges which I believe were unfairly imposed on us at the airport due to a misunderstanding relating to the flight departure date, the steward involved and his manager on the flight were in my opinion totally justified in their actions.
Jon entered the aircraft just before the door was shut and he and his associate were provided the best seats available on a very crampy plane - row 1.
He sat at the window seat and his friend sat in the aisle seat, the middle seat remaining vacant. The cabin crew seemed to be very accommodating to both of them when they first embarked, and it wasn't until he decided to move to the 2nd. aisle just before the plane began to taxi to the runway that things changed.
The steward then asked him to resume his allocated seat as the plane was about to take off, and he refused. The steward then explained to him that once the take off had been completed and the seat belt signs had been turned off [ which he estimated would take between 5-10 minutes] he was welcome to sit in that seat if he wished but because the pilot had "balanced" the plane he had to resume his allocated seat during take off.
He continued to argue, and finally stood up and went back to the front aisle. He then instructed his friend who was sitting in the aisle seat to move into the window seat. Once he sat down in his friend's seat he continued to argue with the steward. I assume they continued to try and convince him to go back to his seat.
Just as the flight was beginning to taxi to the runway the steward and his manager obviously decided that his attitude [which I believe was confrontational to the point of being considered aggressive] was of concern and they communicated with the pilot.
I assume it was the pilot's decision, not the steward's, to return to the terminal and have him removed from the aircraft.
When the plane returned to the terminal the door was opened and shortly afterwards 3 Qantas security personnel arrived, and they asked him several times to vacate the aircraft, which he refused to do.
They then left the plane, and I assume it was they who requested the assistance of the Federal Police officers, who on arrival eventually convinced him that he had no option but to leave the plane.
His "f%&k you" attitude caused the rest of the passengers a delay of between 1-1.5 hours, so I guess it should be him apologising to the remaining passengers [who incidentally broke out into a very vocal cheer when he left the aircraft] for disrupting their travel plans instead of him expecting [demanding] an apology from Jetstar.