The main problem is you dont know what folk are like, some people have a shorter fuse that others. He may well have dragged that fella out the car and windmilled him.
No need for the spit mind you but i can see why the fella who got out the car was (not that i condone such action, was a bit OTT)
No need to be a c**k, be courteous enough and let folk in. problem solved . You dont know what the other fella may or may not be capable of.