Unfortunately, I think the private market has devolved to the point where it's almost expected for either the buyer or seller to be flaky or immoral. It's a bummer for those of us who are old school and still think a man's (or woman's) word really means something, because that results in much disappointment. I've been disappointed here a few times, but it is what it is.
I understand your point, but trust me, nobody wants my jalopies. So, I don't care if anyone knows where I live. It would actually be easier if they saw my car in a parking lot and looked up my plate because then, they'd have my actual address. Just knowing someone's zip or city is incredibly broad and to find out where they live would take a LOT of effort.