I had a 1/2 tank of who knows how old of gas in a /6 truck I bought a couple of years ago, I just let it run out in the gravel drive.
(Currently my "project truck")
Just this past week I dragged home a rotted out 91 Dakota with a supposed dead fuel pump. I parted it out, and scrapped it. Including cutting the tank straps and saving a whole tank of gas. I siphoned off what I could then poured the last gallon or so out, into one of my 5 gallon cans/ filled my mowers, filled the wife's Durango, and still have about 10 gallons of it left. At $5 a gallon it won't go to waste.
Several years ago I dragged home a 76 Aspen from several states away.

Now that gas was way too rancid to consider trying to burn.
As was the gas left in the tank I found in the junkyard for my son's truck, I poured that out in the gravel and smelled that for over a week.
Any gas not as rancid as those 2 or full of water gets burned in another vehicle whether a gallon or 2 at a time diluted with a fresh fill, or to completely top off one of our drivers
Good tip on additives to the Coleman stoves. I'm up to about 18 lanterns now and about 8 Coleman stoves. I had a dozen lanterns lit yesterday on the bed of my truck yesterday, I always have 3 or 4 stashed in the Pop up at any given time.
It's funny when I camp and hear people who walk by and I hear them ask"people still use those?" He11 yeah I do