My view is that the prescription of "carriage of goods for the purposes of trade" is to prevent you from setting up an airfreight business where you buy goods, transport them in your own aircraft then sell them, as a private operation. It is not intended to stop someone using an aircraft as their own transport to get to work.
That was how it was explained during Airlaw however CASA don't see it that way. They seem to be of the belief and as demonstrated here with some of the comments that if you have anything in the aircraft that is used in a transaction then its a commercial operation.
How to deal with ,and rectify all these bureaucratic hide-bound stupidities that have bought GA to its knees...that is the question.
You deal with it by going to court. From what I have witness over the years is that anyone who actually takes CASA on over some of their rulings usually end up with CASA folding like cheap lawn furniture when they actually have to front up to a judge. However the issue is that CASA essentially has a unlimited budget and most businesses don't, so the business/individual just caves in most of the time.