At college, everyone laughed at me because I ALWAYS locked my car doors - but what do you expect from a Californian?
Then, I got a little less conscientious about locking things (like my apartment door when I was home alone - such as the time I had two cops knocking on my door and I just yelled at them to "come in"
)
I don't lock my car doors here in my driveway anymore, but normally when I got out and park somewhere, I am back to locking the doors again - I may live in a small town, but we still have problems no matter where you are.