Although I am a fellow reefer and I am just as guilty for taking wild corals and fish I do not like the fact that the GBR is being torn apart for profit. It is one of the last large reef colonies in the world. Nothing personal and I know I will draw harsh criticism for this comment. I just felt it needed to be said.
I am pretty certain that Australia can manage its natural resources. Perhaps they have a sustainable live rock seeding and harvesting program similar to what is currently going on in the Gulf of Mexico? I think a little additional information might be in order before anyone should toss out blanket criticisms. Having had personal contact with one of the few Australian fish collectors who is actually licensed to collect off certain sections of the coast, let me tell you that the ornamental marine trade in Australia is HEAVILY regulated.
And as far as being one of the last large reef colonies in the world, perhaps you will be happier when you look at the new French Frigate Shoals marine reserve in the far Northwest part of the Hawaiian islands. At 120,000 square miles it is a larger marine reserve than the Great Barrier Reef, and allows no fishing or collecting of any kind. Plus it is located in the United States - which may or may not make you happier.
Personally, I think that live rock is a sustainable resource as long as rock is used to replace rock that is removed. Similar to the numerous artificial reefs created off both coasts of the U.S., when something is placed on the sea bottom, it is quickly colonized and encrusted.
The irony of live rock collecting, is, of course, that many million times as much rock has been dumped INTO the ocean, than removed FROM it. 2/3rd's of the Island of Key West is built on landfill, as is much of the 120 mile Overseas Highway that runs from Key West to Miami. It is amusing to snorkel along these miles and miles of piles of ancient coral block fill, and then be told that all live rock collection off the coast of Florida has been outlawed due to environment degradation. Regardless, if you want to familiarize yourself with live rock sustainability, I always recommend visiting
Tampa Bay Saltwater and read their history (or view their movies).