The Bill won’t mean that every person who provides labour for hire or reward and who is aged 16 or under will need to be paid the minimum wage because there is no minimum wage for people aged 15 and under (see s4 Minimum Wage Act 1983). Ten year olds already have the right to go to the Employment Relations Authority.
Section 18 Health and Safety in Employment Act 1992 already says that principals must take all practicable steps to keep their contractors safe. In addition, r 58A Health and Safety Regulations 1995 extends the protections afforded to young employees to young contractors, which include protections such as a prohibition on young workers working with machinery or doing any dangerous work.
The Minors’ Contracts Act 1969 already says that contracts are unenforceable against minors but otherwise have effect as if the minor were of full age, unless a court decides otherwise. So, if you hire a paperboy as a contractor you can’t actually enforce that contract against him unless a court decides it is fair and reasonable. Contracts of service (employment agreements) may be entered into by minors but courts may examine whether those contracts are harsh or oppressive or unconscionable.
The difference would largely be around Holidays Act entitlements and other minimum employment code provisions. Hopefully not parental leave at that age.