Wow... I can't imagine not locking my bike when I go shopping. It only takes one "incident" to make your day a very bad one. My workplace is thankfully a fairly safe place so there are no worries.

This is *slightly off topic, but I'm always amazed at people that lock their bikes but leave their helmets dangling on their handlebars. During my motorcycle riding days my buddy used to do the same thing. One day someone decided to take the helmet and he was basically stranded 50 miles from his home because he didn't have a helmet. Of course it's different for a cyclist but still...