Have seen figures bandied around of from $6000 AU/block hour to $5000 US/block hour(around $6700 AU) including everything,
You're dreaming, unless you are talking about an ACMI rate.
If they real figures then they would be operating on very slim margins - a recipe for going broke. As has been pointed out, fuel cost per hour is not cheap.
What exactly is the "everything" supposedly included?