It seems that whenever I am driving I've always got to pick my nose. I've also noted that other people do this on a daily basis as well. Why do people have the tendency to pick their nose while driving?
I suppose one explanation of this observation is that being a driver in a car is a semi-private space. It is semi-private in that it often feels like people can't see you. In addition, even if someone sees you, you will be driving away from them shortly. And it is unlikely that they know who you are and that your nose picking will ever affect your reputation.
Thus, presumably there are many activities that people tend to do more in private, that occur often in a car. E.g., random singing, farting, etc.
Because it it socially unacceptable to pick ones nose. However, we all do it at some point or another. Whether there is a tissue directly involved or not is another story.
Also, typically people are alone in their car and due to "social inattention" (also called civil inattention https://en.wikipedia.org/wiki/Civil_inattention) they may assume that no one is paying close enough attention to care. Even if they do, the chances that it is someone they personally know are typically low (depending on various factors such as size of the city and neighborhood etc.) But, I'm betting that most instances happen outside of the proximity of one's neighborhood. I'd like to see a statistic on that one!
I think the one contributing factor is that when we are in our cars we may have the vents pointed at our faces or the windows rolled down. As we go about our day it probably isn't too often that we have a stronger wind source blowing directly at us and as we breathe in we may start to notice that our nasal passages are a little blocked up. Perhaps the added force of the fans or wind as we drive really push the mucus (and whatever dust or dirt it stopped from getting into our lungs) and stimulate the hairs in our noses which causes a mild annoyance. Probably why we know exactly where to reach at it first.