Yeah, but you see how thin that wire is, the current going thre it must be tiny, so even though the voltage is very high when it ars over the current isn't high enough to expend a huge amount of energy. I've seen pictures where high voltage arcs in substation formed with busses or transformers which can source billions of watts in fault conditions (yes, 1.21 "Jiggawatts" would be easy for them), and I highly doubt a cars thin metal exterior could save you.