Question for you Jaba,
Do you carry an alternate on all your flights or 60 mins fixed reserve and another 45 mins on top of that., as that's what you are saying these pilots should have taken and what you would expect others to take, when the forecasts say the weather is good.
My ops are not RPT, and usually I have so much fuel it is not a problem. I almost went to YSDU/YNRM yesterday, but realising the holding/alternates and expected wx may have meant returning to Brisbane, I cancelled, was not worth the effort, and I would have arrived back here with 1.25 hrs fuel even after doing a MA. So my fuel policy/capability is not relevant o a B737 operation.
You ask why they didn't land in Melbourne, have you looked the Melbourne weather on the day, it was crap!
indeed, but was MEL closed? Or were there ILS ops in use with legal landings?
If a passenger asked how much fuel I had on board I will call the AFP have them removed, as I would consider that request as someone who is unstable and could be looking at using the aircraft as a weapon.
Unstable? yeah and how well would that hold up, I thought the pax was unstable 
I think I would have just the same amount of success alleging you as the Captain were equally unstable and definately had the access and ability to actually use it as a weapon Vs me down the back. FFS if you are going to take shots at me do better than that.
Even under the old system of ATC operational control, the ATC Ops controllers would not have question the departure fuel as there were no requirements at the time. What would have happened, once both aircraft were airborne and the amended weather for Adelside appeared this would have been relayed to both aircraft via the sector controller.
Again, min fuel Vs prudent, knowing what ADL and places can be like at that time of year? It is a judgement call, Captains discresion. So why then would plenty of folk who actually captain these things into these ports say they always carried more under situations like that?