I believe that it is certainly your right to expect just a bit of decorum in F. The purser should have backed you up but unfortunately they probably realized early on the futility of expecting decorum from those who are completely unacquainted with the concept. Somewhat like trying to dress a pig in the mud. Lots of people will get muddy. Face it, flying is not what it used to be and I too have seen folks getting on the plane in HNL that I was sure still had sand between their toes-and maybe in their bathing suit too. Fortunately the slobs weren't sitting near me!
Sorry you had a bad day. We all have our horror stories! My worst was LGA>LAX many years ago.....