Spot on with the difference between politeness and respect. I would say that the two are often correlated, but there's is no causal relationship. In my daily life, I am often polite to people that I respect very little (out of expedience at work, for example), while many other times I'm down right rude to people I care about and respect (like when I harp on my sister to get in the gym, for God's sake). Politeness is a very overrated quality, and often times, it causes as many problems as it solves (such as when we're timid about expressing our feelings, because we don't want to come of as an asshole, even though we're sure we're correct, an experience I'm sure everyone can relate to).
Haha, yeah I know what you mean. Sometimes the worst insults come from the most polite people. I have the feeling that our customs of expressing respect somehow devolved into mere politeness, but that those courtesies were originally intended as a neutral starting point from which people would then be able to to learn about each other more. I've read theories on how waving and shaking hands are both intended to show others at a distance that one is not armed or that one is not hiding a weapon in one's sleeve. Similarly, the clinking of glasses is intended to show that there is no poison in one's cup, by allowing the liquids to slosh into each other. However true those theories may be, I think that politeness has its place; but as with so many things, we've taken it entirely too far. This is another reason why I think it's a good idea to travel while one is young. In many countries, what I would consider as merely polite comes off as overly formal and impersonal. There are places where saying "thank you" is a bit offensive, since it implies that one did not expect to receive generosity or hospitality, which in some cultures is a big no-no. Even among friends, these layers of politeness and the desire to give others space out of social custom or respect are different elsewhere. I heard a good example on the radio a while back from a man from Africa who said that the difference between people in America and his home country are how people would react if a friend came into their home and woke them in the middle of the night. In America, people would be perhaps a bit upset that their friend had entered their home without permission and had woken them, asking, "what's wrong?" and other questions before deciding whether or not to help out. In the man's home country, a friend would put on their clothes and simply ask, "where are we going?"