Smoking a cigarette.
I'm willing to withhold judgement, because I hope it is not intentional.
The fumes are actually what ignites, which is why even talking on a cell phone while pumping gas can be dangerous. But, you can douse a lit cigarette on the ground with gasoline and put it out.
You observation of the man and his gas cans speaks to the number of folks on the left hand side of the bell curve