Ok, now here's a question for those of you that have rotopax/jerry can /or other fuel container... How often do you ACTUALLY use it on your rig? Beyond filling auxiliary toys( atvs /dirt bikes /generator etc,) it seems to me having to actually use it on your rig is simply poor planning.
With a 20 gallon tank, assuming offroad/idling mpg of 5mpg(guess, probably higher) , and say 20 miles at 20mpg from nearest gas station to where the pavement ends ...that should give you 90 miles of offroad fun, 45mi out 45 mi back... I find it tough to believe the need for most "overlanders" to have the extra fuel. But hey what do I know.
Poor planning? Not at all. Poor planning is not taking it, even when you think you won't need it. Someone else might.
The Mojave Road, Death Valley, or any remote desert location calls for extra fuel. If you don't carry it, you're asking for trouble.
A winter day run up a mountain, I carry fuel in case I'm stuck on the trail. I would rather use extra fuel to run the engine and keep warm, than rely on the sleeping bag and blanket.
You might be close to gas on a multi day trip, but having it with you means you can stay at camp and not pack up to get it. You can also run the engine to recharge the battery if you don't have a solar panel.
Going out of state and getting different ethanol mixtures can cause engine issues. I've seen it going from CA to OR. Add some gas from home and the truck (an LR3) fired right up.
Gas can get expensive, and it doesn't have to be 100's of miles from civilization. Bringing your own can save you some money.
This picture is from Panamint Springs, Death Valley back in 2013. That's $6.289 per gallon for premium! My D2 holds 25 gallons of fuel. Thankfully I only had fill about half the tank.