Ah, remember the good old days? You could go to the gas station with a one gallon glass vinegar jug, fill it up and no one would notice. They were nice to use for filling chain saws and small gas engines, because of the small neck. Never had an incident with one, or the 2.5 gallon oil cans motor oil used to come in. If you tried that now, you would be surrounded by a SWAT team in no time!

I  don't know if they are still available, but they used to make a locking funnel for putting gas/diesel in the older tractors. The funnel would lock onto the top of  the tank like the gas cap.

The best way to start a charcoal grill or BBQ cooker is with one of those propane weed burners. Coals are ready in no time.