IMO, be a little more careful in where and how you leave your bikes.

At work, I take my bike inside, and right next to my cube. When I am out, the only time my bike gets locked up is when I can EYEBALL it. In other words, I am looking right at it while I am eating or whatever. If I can't see it, it comes with me. I commute 5 days a week, and ride on the weekends. With my method, no bikes stolen.