Yeah politeness associated with "goodness" is like associating beauty with "goodness". Anyone with sense knows they aren't even slightly correlated. Politeness looks nice, but can be Machiavellian or it can be good. It really just depends on how its applied.
Important counter-point: http://gawker.com/on-smarm-1476594977
The idea that politeness is what divides the do-gooders from the bad ones is, I think, part of what got us into this mess in the first place.