Maybe I'm missing something, but what's the fixation with a huge fuel tank?
Unless you're traversing the Simpson desert everyday to work, or every time you go on holidays, when do you actually need to carry 180L of fuel? Most places I've travelled to around Australia where it's considered 'remote' there's usually fuel stops every 200/300km. The reality is if you're doing long hauls you have to stop occasionally anyway - toilet breaks, stretch the legs, check the trailer. For me it's not really an inconvenience having to pull into a servo and topping up the tank after travelling 500km non-stop.
I've a couple of mates who own Prado's with the 'big' tanks, and the irony is none of them fill them up very often cause they reckon it's a waste lugging around all that fuel! They'd probably be better off with a fuel tank half the size!
Not having to carry extra Jerry Cans of fuel when we go somewhere remote. 4 jerry can holders on the camper = 80 litres more water
Sydney to Dubbo and back without refuelling - just cause I can.
Paying for fuel at Alice springs either end of an Uluru trip and not at Yulara resort so not paying the extortionate fuel prices
Being able to fill up in major towns and not road houses - 10c differences in fuel make a big difference in a 180L tank
Fill up Harrietville then head up in the Vic High Country for a week of driving and return to Harrietville without having to make the hour round trip to refuel
Fill up on the mainland, drive over to Fraser and not worry for the rest of the week about fuel stops - fill up again back on the mainland
I fill up around Sydney every 4-6weeks so I can wait for the cheap prices and/or take advantage of shopper dockets to get 20c off fuel - 180 litres @20c cheaper saves me $30+ a tank. I don't buy into the lugging around the extra fuel argument. The car gets driven almost every day so fuel is pumping through the system so little chance of algal growth
We go to a campsite every xmas for 2-3 weeks that has a lot of 4wding around it. Its 15km to the nearest road/house servo and fuel is 10c more expensive, or its 30mins to the nearest town to get fuel so again one less thing to worry about.
We drive to the south coast every month or so. I can fill up at the bottom of the cycle and then do the 700km on single tank at Sydney not rural prices.
Would it kill me not to have the large tank? No, but its nice.