[anenefan]

I think it is for the more obvious reasons on the way big important business end of town (esp those which are new to Australia) would like to operate here in Australia. It's guardrails so:

  Non competition  for existing power and upwards pressure on pricing - thus avoiding additional cost of living for the general public.
  
  Discourage simply purchasing an existing power utility.
  
  Those investing for profit in these centres don't move to areas where transmission lines are already  near capacity with a buffer for the next couple of decades.

  Don't build the centre in a more rural setting (where there's water) with expectation above ground transmission lines will just have to happen, and expectation planning and land leases of nearby rural land to place the lines will just happen with minor cost to them but with no regard of the community which will just have to take those lumps.