I'm one of those people who HATE it when someone swipes something from my desk. Normally, I'm generous and will share just about anything. But, if you value your hands, don't steal my pens, pencils, or stapler. You can take food off my plate but don't you dare touch my paperclips. (Especially the red ones--they're my favorite.)
Boundaries. That's what stealing is about. Or, rather, a lack of boundaries.
I would never dream of opening your desk drawer. Or swiping a pen from the cup on your desk. Of course, as a writer, I'm always carrying a dozen or so pens with me: in my handbag, in my car, in my briefcase, even in my checkbook...
Seriously, I can't remember stealing anything. I've never even been tempted. I don't understand the motivation.