I discovered today that you don't have to let virtue be its own reward when it comes to bagging groceries.
I have cloth bags from local stores as well as places like Trader Joe's and Whole Foods that don't have locations in Northern Clime. These aren't the fashionable "I'm not a plastic bag", just the regular ones. Usually they grace the floor of the car, since I rarely remember them until I'm standing at the checkout counter, when it's too late.
Today, as I was walking into the store, sans bags as usual, a girl yelled, "Stop! Don't make me carry that!" Turns out that she was yelling into a cell phone, and, with the clueless voice-volume-up-to-11 habits of a cell phone user, had no idea she'd made me jump. Somehow, though, in my sleep-deprived state I took this as a direct message from the bags, turned on my heel, and got them out of the car.
Did you know that the store gives you a 5-cent credit for each bag? I didn't. I guess I hadn't been paying attention when I've used the bags before. I know it's just a token (it was 5 cents back in hometown fifteen years ago, too), but it's a nice token.
So, to answer an age-old question: virtue is not its own reward. The reward of virtue is (drumroll) 5 cents.