Politeness has a bad name. We often assume it's about being 'fake' (which is meant to be bad) as opposed to 'really ourselves' (which is meant to be good). However, given what we're really like deep down, we should spare others too much exposure to our deeper selves. We need to learn manners, which aren't evil, they are the necessary internal rules of civilisation. Politeness is very linked to tolerance, the capacity to live alongside people whom one will never agree with, but at the same time, can't avoid.
From Alain de Botton's A manifesto for atheists: 10 virtues for the modern age.