How exactly do you think you know what class people are flying in from how much they eat or drink?
If platinum members (and let's not forget that Qantas has said they built the first lounges for us platinum members) were only allowed to use the business lounge, there would be bugger all difference between gold and platinum, and I for one would probably not have ever bothered trying to requalify as platinum after I stopped flying for work so much.
On the broader issue, I always figured the first class status credits from AA were too good to last. It's been great while it lasted though - I requalified two years using AA status runs.
I'll make a few observations...
1) If you were to plot on a graph how much pax were effectively paying per status credit, you'd likely find the 'AA runners' as outliers at one end of the image. Restricting the entire program earn because of outliers would be a poor decision for multiple reasons.
2) Pax holding gold/plat status spend more. More on airfares, more on the ground and more on disposable income type services in general. This is good for QF.
3) These outliers who have nothing better to do than go to the USA and do runs are making a significant investment in doing so. There is the multiple days of your life spent flying, overnights and a soul destroying experience in domestic US travel. For these reasons, it will never become mainstream.
4) Status members are more likely to be earning credit card points. This, in many instances, can be more profitable for the group than flying.
An important factor to remember is that status is how YOU perceive your rank/value with the airline. The airline/FFP ranks you very differently to pure status. Most airlines, including Qantas, have scoring systems which dynamically change every day depending on your activity. It's possible for a Bronze member to be more valuable to Qantas than a Platinum One member.
Factoring in the above, and that frequent flyer points are even easier to obtain now than ever before in history; if anything - we're heading towards status becoming even easier to obtain.
