I rode to the neighborhood grocery store to pick up a pound of coffee, we were out. I got to the store & relaized I had forgotten my lock. So, I could either ride home and get it, or keep my eye on the bike as I got the coffee. I figured I'd do the later since I could see the bike from the aisle where they kept the coffee and also while I was paying for it. Sure enough some kid comes by, grabs the bike and tries to start down over the curb with it. But, the front wheel drops out when he lifts it to take it over the curb...... because, I've gotten into the habit of releasing the front quick release on my bikes even when I lock them up. And the back wheel won't turn. I've also gotten into the habit of setting the brakes on the rear wheel so that when the quick release lever is in it's closed position, the brake pads are very tightly pressed against the rims. I started doing these things 30 years ago. These days, however, you have to file the lawyer tabs off the front fork dropouts. In any event, this slowed him down just enough for me to head out the front door of the store and confront him. Actually, he saw this old guy racing out of the store with a bicycle helmet in hand, and he just dropped the bike and ran.