How do altruists cope with their own moral hypocrisy?

Since learning about the egoism of the Objectivist ethics, I've been fascinated by how often morally righteous altruists -- who live with their ideas and push them on others -- are able to maintain a seemingly high level of psychological strength, self-esteem, and motivation in life. I'm thinking of the kind of altruist who achieves a high standard of living for himself and his family and who pursues a career of his own choice. Many politicians are good examples of this. The Objectivist ethics seems to say that these individuals should not be able to exist. How do they do it? How do they get away with it?