QF charges way over $10K for their business class LAX-SYD rt so there definately is something worse than the $8K popping up on your screen.

But seriously the $8K are full fare J fares that many have already stated. You can go to a consolidator that offers D or I tickets for considerably cheaper price starting at around $5,400. Just start being active in picking up the phone and start calling or emailing. Or if you don't mind doing a little detour, you can always route via SFO or YVR where CX business fares are $2,500-$3,500 cheaper compared to LAX as CX does publish the discounted fares on their site ex-SFO & YVR.

Premium class pricing ex-LAX or ex-JFK, regardless of carrier, are never cheap. Take BA's $14K JFK-LHR fare for F which is more expensive than CX's $13K rt LAX-HKG fare for F.

My agent in Toronto has given me a CX "A" fare quote via JFK for CX831/830 rt to HKG (YYZ-JFK vv on AA) not long ago and the fare is at around $9000 USD. But to take advantage of this fare, one HAS to originate from YYZ. If one originates ex-JFK, the fare skyrockets to $16K. Basically airline charges what they believe they can squeeze from the consumers' pockets rather that what it cost them to operate a business or first class service. And this is one of the example where regardless whether the passenger is originating from YYZ or JFK, they are getting the same plane & same service on the CX flight but the point of origin means all the difference between paying that extra $7K.