Aussie here, we try to get both the .com and the .com.au (and now also the .au), because people will just use one or the other, regardless of what the link says.
Investor value at the cost of hurting small business by increasing cost or creating confusion.
I've had a .net.au since 1999 and the same rules apply there.
People in Australia use .com.au all the time, domain.au almost looks broken to my eye.