Underwear

You buy one pack of tighty whities on a whim. Gradually, over the course of a month, all of your boxers just seem to dissapear. Now, you just are someone who wears tighty whities all the time, because he has nothing else to wear. This is how fundamental changes in your identity happen, through some kind of bizzare moral drift inherent in the nature of having things. Only a true act of will, and a trip to Walmart, can reverse the cycle.