Are chelsea FC to polite?

It seems Chelsea fans are not the hooligans they used to be back in the 80's, I have been to a handful of games including champions league and derby matches against rival teams, and the fans don't turn up the volume to try and intimidate the other side, they don't shout abuse at the other side's fans and talk amonst themselfs rather than stand as one, don't get me wrong they so support there side and show respect and stand when a goal is scored, but not really what man untd. or liverpool fans offer to the team like a 12th man why is this?