LoL, these posts crack me up.
The reason? You assume talking to a car model is somehow different from talking to a girl that's frumpy or not as societally attractive as others. It's not. A car model has the same feelings of insecurity, doubts and fears about herself that ALL girls have. You have to remind yourself that her looks are simply an outer shell that's hiding who she is, nothing more. Once I was able to get this into my head (and, admittedly, living with a drop-dead gorgeous girl while in school who also had irritable bowel syndrome and was messy as heck helped my viewpoint on "hot girls" become a LOT more realistic), I had no problem talking to ANY woman whatsover, regardless of what she looked like.
In answer to your question: you don't go in there trying to ask any of the models for a "date." You go in there with the hopes of striking up a conversation and getting the number. If she agrees to give you the number it means she's open to you calling her for a date; if she doesn't, it's her way of saying "no" to the idea of dating you in the least harmful way possible. Hope this helps!