In Australia when a speed camera takes a picture of a speeding offence, or a red light camera, it records the registration plate of the offending set of wheels.

A letter is then sent to the registered owner of the wheels.

IE: the rental car company in this instance.

The letter contains the fine, it also contains the section where it talks about the registered owner being the driver, but if you are not the registered driver you are obliged by law to indicate who was driving at the time of the offence.

So rental company checks their records, sends off the fine with the renters details, and the fine goes away for the rental company.

Infringement processing branch then sends a fine to the registered driver.

After a few reminders the fine goes to in NSW the Department of State Revenue, who follows the unpaid fine up.

It might be registered with Immigration - but I doubt it.

A few years ago NZ changed its rules, and started loading Immigration records with unpaid fines totally $5000 for any individual.

My guess is if you have one speeding fine you won't get suckered into paying it, but if you have a bundle you might get caught.

However for the ease of future international travel, it might be a good idea to just pay it.