Yes, someone was actually fined for hogging the overtaking lane

AutoExec Summary
New South Wales Police reminded motorists to stay out of the right-hand lane on certain roads after a provisional driver was fined for disobeying the “keep left unless overtaking” rule on Sydney’s M5 motorway. Despite passing an electronic message board emphasizing this rule, the driver continued to stay in the right-hand lane, even with a patrol car behind them for 3km. The driver received a $410 fine and two demerit points for the offense. This rule applies in New South Wales, Victoria, South Australia, the Northern Territory, and Australian Capital Territory, while Queensland and Western Australia only require this on roads with a speed limit of 90km/h or higher.

Brands mentioned: Sydney’s M5 motorway, Liverpool Highway Patrol, New South Wales Police, Queensland, Western Australia, Victoria, South Australia, Northern Territory, Australian Capital Territory.