It is wrong to take someone's gas.
Carl was mowing his lawn when he realized that he was out of gas.
Carl wants to finish mowing the yard.
Carl goes to the gas station and buys a few dollars worth of gas.
Carl goes to his neighbor's house and siphons the gas from his lawn mower.
Carl fills up his lawn mower and is able to finish his yard.
The police arrest Carl for trespassing and theft of the neighbor's property.