In the early 90s, a helicopter was used to bring bank docs to Sydney from Gosford and the Central Coast. The docs had to be in SY by 7pm. In winter, the run was done Night VMC.
A jealous competitor in the chopper business decided to be an R-sole (well, actually it wasn't a decision, he was an R-sole all the time) and put his own aircraft up at Long Reef at 6.55pm and "perform airwork". Along comes bank runner, asks for clearance, it is not available due to R-sole taking up too much space, delays, anger, multiple requests denied, until R-sole has kept the bank runner out past his deadline.
This went on for 3 nights until a quiet word with ATC by phone alerted them to what was happening, so when R-sole requested takeoff clearance at KSA, tower held him on the ground until the Bank runner was home. R-sole was spitting chips at ATC, but they knew what he was like and just laughed.