A lot of people here are misunderstanding the phrase. People who do not drink and drive are not "holier than thou". People who would stop to render aid to someone they have injured are not "holier than thou", they are responsible citizens. The term "holier than thou" applies to those who have never been in such a situation and respond emphatically, knowing exactly what they would do, as if they were. They believe they would have done the righteous thing, no matter what the circumstances, when in fact unless they were in that situation they will never truly know. It's kind of like an Monday morning quarterback (God knows we have a ton of those on this board), this person says the Bills should have done this or they should have done that, not really knowing if that would have worked or not, but it's much easier to make that statement after the fact.