They aren’t changing the track or modifying the steering components.
Can’t see why they would be illegal.
They correctly centre the wheel on the hub to stop runout.
In the vicroads website, I found this:
This is supported by a requirement in the National Light Vehicle Modification Code of Practice (VSB14) which is called up in Victorian legislation that states “Replacement aluminium alloy rims must be located on the hub/axle by the same diameter centre spigot as the original wheel, using metal adaptor rings where necessary”.