The Industry

"I understand the risks involved of someone without the knowledge and experience to use lighting equipment, however i don't understand why it is said that it is illegal without being trained"

I'd certainly check that with techies in your state before relying on that comment - they might be covered under laws concerning trade industries. For example, it's common in most states (to my knowledge) to have laws preventing people from working as plumbers, electricians, boilermakers etc without having the proper qualifications. That's not because a piece of paper is better than experience - in fact for most trades getting experience (as an apprentice) is a required part of getting that piece of paper. It's to protect consumers by allowing them to have confidence that if they hire a plumber, electrician etc they can rely on them being competent. It's a lot easier to check someone's piece of paper than it is to check whether they actually have all the experience that they claim to have.

It might be the case that some techie work falls under the laws relating to these trades, and hence requires certain certificates that you can get from doing the WAAPA courses. I wouldn't have a clue whether this is ACTUALLY the case, but it certainly seems possible, and so its worth checking out before you take the risk.