I live in NW NJ and I always lock my car and house. Partially for criminals, partially for the local wild life. There is an extremely low crime rate in my area (around me, most intruders would be greeted with buckshot if they broke into a home). I could probably get away with leaving my car unlocked when I am out and about, but its the non-locals who I worry about. We have easy access to highways and the NJ/PA state line is under half and hour away so I always keep it locked.
On the topic of wildlife: A buddy of mine left his phone out on the front passenger seat and a bear thought it was something he could eat... Long story short he need a new passenger side door, a some bodywork, and a new phone
Bryce