If he was as blind as he was clueless and didn't know he spilled it on your X then maybe he gets a pass but he still bumped your mirror and wouldn't even say sorry or anything.

If he did know he spilled it (hard to imagine he didn't) then he is among the lowest of scum and a big chicken on top of it.

Fortunately wax is all you need to fix the spot after it has been washed.

That is the kind of thing that seems to happen to me too, no matter what I do to park away from others or to try to avoid issues, BS happens, nothing else one can do if they drive a nice vehicle to to avoid it.