Yes, this is a funny phenomenon. Don't recall ds doing this, but dd4 still does. She almost always had a car in hand from 2-3years, and has a pretty big collection. It was like in 'Conspiracy theory', where the guy has to have a copy of The Catcher in the Rye in order to feel ok. If we were at the store and she didn't have a car, we'd usually end up with a car. Thank goodness they were usually 98 cents.
Anyway, now she always wants to have something 'to point with' as she puts it. If we are getting in the car she will make sure she has one or run in to the house to get something, a Popsicle stick, pen or something else about that size. I wasn't sure why, but today she said it is because she wants to be a teacher. Fortunately it has gone from a very high level of 'need' to much milder 'need'. (nowadays if we can't find a pointer she might be able to survive until we get home )