I too am curious about this.
Years ago, in my pre-editing days, I used an agency called Avid Special Agents when I needed to find editors for projects. I think they have since changed their name to Crew Cut, but am not sure if they are still operating and if so to what capacity.
I know there is a trend against editors using agents in Australia and can understand some of the reasons why (mostly being financial). However, I used an agent for the five years I worked in London and for the most part found it beneficial. They not only managed my diary, but found me work, negotiated good rates, made sure I got payed, and importantly, they protected me against unfair working hours, making sure I was payed for all overtime and weekend work at the correct rate. They also made sure that if I did work long hours, the client fed me and organised / payed for a taxi to get me home. They also had a strict procedure in confirming jobs, meaning measures were in place in the event a job was cancelled after it was confirmed.
All in all it was a good experience, but I assume the smaller industry in Australia doesn’t allow for this type of service.