It's not particularly cheap (A$24.95 per parcel, plus A$5.95 per 500g, in 500g increments
https://shopmate.auspost.com.au/our-...shipping-rates ), and there are numerous cheaprer "drop shipping" companies if you're game, but I imagine a lot of people will feel more comfortable signing up with Australia Post than some unknown (to them) alternative. It's probably not competitive for small purchases (especially if you can find the item on eBay or similar with free or low-cost international shipping), but for items where there aren't any vendors who ship to Australia, it could be handy.
Add it to a free 24/7 Australia Post Parcel Locker
http://auspost.com.au/parcels-mail/p...rcel-lockers-1 (if they have them in your area), and it's a pretty convenient way of shopping on-line, without having to wait around for the courier to knock at the door.