So, let me get this right...She looks down her nose at you, being "middle-class" in her opinion, and then she walks out to her nissan? Sounds like someone needs a reality check. It shouldn't matter who you are, or what class you are for that matter, there's a little something called "equality" that everyone should understand.
Perhaps you should slip a beer into her car for her, and then notify security. I mean, you do need to handle this with class, after all.