These are some pretty eye popping rates. I travel within Asia quite a bit, and I know the LCC's often charge $10-20 for a 15-20 kilo bag. Australia carriers certainly sock it to you. Luckily, for leisure travel, one 20kg bag is usually fine for a couple. That's what we did last year flying between SYD-MEL.

I do regularly take 2-3 bags at 32 kg each back and forth to the states, mostly for business. At worst I pay $150. Flying on Biz and FC awards and jumbo fares does have its advantages, I guess.