Gasoline smells completely different than diesel. Is the can green or red? Red=gas Green=Diesel.
Well, it smells like gasoline, and it was in a red can, but the latter doesn't mean anything, they could have used a red can for diesel, out of necessity.
It's just a gallon of gas, not worth taking the chance. I'll make it a point to put it in the trunk the next time I'm out that way, just have them dump it, get the can back, wash it out and let it dry, problem solved, and I've got my free jerry can. A lot of rigamarole to go through just for a freebie.