Well aware of the points purchase systems. However I have not heard anything about status system purchases. If this was available, why wouldn't QF sell status to numerous other vendors (whether that be top-end CCs or similar)?
Personally, I don't think this exists - due to the immense costs that it imposes on the airline. The fact that only a single OW airline has this as an option (and even then, for a single year only) supports my case. Happy to see what evidence you have to support the opposite argument.
Expensive doesn't mean that the fare is profitable. QF has stated publicly (and this means that is must have some legal basis for the statement - or be guilty of misleading the market) that it's international arm is non-profitable. Each "visit" to the F lounge will probably cost QF more than it's making on any cheap fare IMHO
QF are welcome to fly that international flight with or without a bum in the seat. Whether the seat is profitable or not if QF's business. But I'm sure they would prefer to fill it vs not filling it. And the additional revenue from the seat is still more than the consumption at the F lounge (JQ35 excluded).
Not sure what you mean by "only a single OW airline has this as an option".
All airlines that you can earn QF SC's on (as per the Airline Earning Table), have a commercial arrangement with QF for the SC's. (just as with points). And vice versa for airlines for which QF flights allow their FF's to earn status.
Not restricted to one year, nor one airline.
Why can't you buy status with your CC? Because status is the one thing that differentiates a Frequent Flyer from a Frequent Spender. (As you already know).
With regard to AA status earners:
1/ You can fly AA as an AAdvantage member, get AA status, then use that status on OW airlines such as QF for benefits.
AA gets the revenue, AAdvantage bears the cost of the points/status earned, and when the AAdvantage member uses a QF lounge - QF bills AAdvantage.
2/ A QF member can fly AA.
AA gets the revenue. AA reimburses QFF for the cost of the points/status.
When using an AA lounge
- AA bills QFF. When using a QF lounge, QFF bears the cost.
3/ A QF member flys QF. QF gets the revenue, QFF bears the cost of the points/status, and when you visit a QF lounge, QFF bears the cost.
Either way - QF isn't a charity, and they are getting paid one way or the other, regardless of whom you fly.
The program to whom you belong pays the lounge visit costs.
As far as the exact amounts of the transfer payments in the commercial arrangements? Top secret stuff there - but I doubt that anyone thinks that QF would screw themselves over