But if you look at just the number of people in the lounge at any one time compared to the total number of QF/JQ seats on all departing flights within a 3 hour window, for example, there are not many at all. Entire sections of the lounge are often empty, and I have never seen the dining room more than 1/2 full.
Sydney though is different. I often have to sit at the bar to eat because the restaurant is full....
So maybe not as many WP based in MEL? That is a possibility...
It would be impossible to make any sort of real estimate based on some visits to lounges, for the pure reasons that:
1. Not everyone who visits a lounge actually has any status, it's entirely possible that the visit is the result of either class of travel or service recovery
2. Not everyone knows what their actual lounge entitlements are
3. People can travel in groups where-by they remain outside the lounges as they don't have enough guesting rights
4. Some people turn up at the airport with a minimum of time to spare (thus no time to access lounges)
5. Some people just never travel internationally / never Qantas internationally
6. There are numerous lounges around the world that a person with status might be found at, especially for an airline like QF that does not have a hub which all pax are funnelled through. QF is not like SIN with SQ, HKG with CX or DXB with EK. Domestically AU is very much a mesh, and even internationally there are four ports which they operate international flights from.
7. Assuming that all the above variables didn't apply, you'd still need to monitor the entry / exits' of the chosen lounge, over various times of day, and days of week, and then monitor the number of people going to the lounge and onto flights and compare pax numbers from the lounges vs not from the lounges, and no-body's got time for that.............. except QF, who would monitor that diligently, as it's their business to know.