• Reduced flight hours and maintenance on fleet aircraft.
• Instructors do not need to be pulled from schedules.
• Fleet aircraft do not need to be hard scheduled.
• Cost per flight hour is much lower for common aggressor platforms (A-4, L-39, F1M, and now these legacy F-18s) than the aircraft the Air Force is training in.
• Private companies can more easily maintain and source parts for aircraft the military cannot (Migs, for instance).
This particular sale was the remainder of the RAAF's retired F-18 fleet, which Canada started buying in early 2019. These are _not_ Super Hornets.
Some of these companies have been around for decades. Some competitors:
• ATAC
• Top Air
• Draken