The chute prevents the requirement to have a pilot in the aircraft to keep it straight and level. Disadvantage is that if the aircraft is jettisoned from the helicopter it will pretty much plummet to the ground whereas if there was a pilot in it, the aircraft could be flown to a forced landing area.
I's all about safety and risk mitigation, as per the CASA requirements.
There are a few questions about this in the CASA exams.
Pilot will also be able to log the hours as well.