Well, it seems like there's a fair bit of BS flying around here ...
You cannot seriously say in anyway that she could see this coming. Also how many people ACTUALLY take off their keys for valet, even though I have two sets I still tend to use the most handy set. (Those who have never used valet ... truly you cannot comment on it).
Okay, she could have gone to extreme lengths, but why would she do that? This is more than an open and shut case. This guy wasn;t a known nut, no screening would pick him up.
Maybe she didn't learn her lessons in the lifes hard schools, and was totally savvy from it, but that's no exscuse.
Lets look at it this way. The guy was paid (in part) to park her car for her. There's a trust there that that will get done, and only that. It's no different (in many ways) to someone taking you cash fr say a ticket, then printing a fake and taking your cash. It's all about trust, the job function isn't thtat important.
P.S. Give Kremit a break, he's pretty much on with the over-reaction'ism of this. Can't blame her one little bit IMHO.
