One of the things creationists teach us everyday is that people have little difficulty convincing themselves of the truth of whatever it is they want to believe. You don't believe you're a thief, and as with most people, what you believe is good enough for you. Most criminals are prime examples of the need for people to believe good things about themselves even while committing heinous acts.
Artemis Entreri writes:
Yes, but mine is petty, so it’s no biggie.
Like the girl in the old joke, we've already determined what kind of person you are, now we're finding out the price.