Acceptable of course, but that is not the scenario.
"You park your SUV in a space and you and your wife prepare to do some shopping. You open the door and a 300 pound jerk is near to the vehicle and he slams your door shut and yells at you and tells you to leave, and says your kind don't belong around here. You get out of the vehicle...."
That's where I (and apparently many other posters) part company with the scenario. If I cannot exit my vehicle with suitable clearance I do not exit my vehicle. My vehicle is my first line of defense. It allows me a degree of armor against attack, it affords me means of escape if necessary, and it buys me time.
My first priority is my safety - I can't defend my wife/children/parents/etc if I am disabled. If the perp is already within the red zone then I would be a fool to exit my defensive parameter and confront. Once I've reestablished a safe zone then I can reassess the situation.