So essentially each outlet/restaurant is like a single lounge. You can "visit" once a day and get the $36 credit. If you have Priority Pass with free access and free unlimited guests (like the Chase Sapphire Reserve Visa), then you and each guest gets the $36 credit at each restaurant. That's quite a deal!
So, if you have a Priority Pass with guesting privileges in Terminal 1 taking 2 guests, you could potentially spend $324. ($108 at each of the three outlets).
For reference, here's some more details from PriorityPass.com listing for each outlet:
[h=4]Conditions[/h]1. Cardholder upon entry must present a valid card to staff who will swipe and record the visit including accompanying guests. 2. Only guests registered as accompanying the Cardholder are eligible for AUD$36 per person per visit off final bill. 3. AUD$36 is non-transferable & cannot be exchanged for cash substitute or refund if final payment is lower than AUD$36 per person per visit. 4. Cardholder is responsible for the remaining balance should total final bill exceed AUD$36 per person.
[h=4]Additional Information[/h]5. AUD$36 offer is valid to purchase any type of meal and/or drink. 6. AUD$36 per person per visit will be deducted from the total final bill. 7. If the restaurant is unable to grant the credit, under no circumstances will an offer of compensation, cash substitute or similar be provided by any party. 8. Please note that the restaurant may exceed their seating limit at certain times of the day and access to the restaurant is at the restaurant’s sole discretion.