I find riding is somewhat of a habit. I find myself not even thinking car or bike. If the habit is car, then I just walk to the car, if it is bike then I walk to the bike. I have often found myself with too many groceries somehow "forgetting" that I was on my bike and didn't have the car. A gallon of milk will fit (barely) inside of my riding jacket, but the ride isn't that fun! So yeah, I sometimes don't ride, but more out of habit than choice.