Rep,
In a nutshell, yes. If they run down the airspace boundary and are within nav tolerances, then we just monitor. Its the ones that blast on thru that cause the dramas.
Yes, the report goes to CASA and they decide what to do. Most, we never get a callsign, so nothing happens. If we do get a response we usually get the PIC to give us a call when they land, have a chat about where the stuffed up. That also goes in the report and if CASA are happy, its left at that.
Obviously if there is a separation breakdown or passengers are put at risk, things may get worse but I think that is fair enough.