I have, I just never saw that as something related to "filth".
The word filth makes me think of dirt, grime, grit, germs, that sort of thing.
In the original posts's quote 'filth' was defined as "lowlifes and criminals". Which is a desperately middle-class concept (middle-class in the bad way), reeking of insecurity and the irrational fear of the unknown (= ignorance).
A little bit like germophobia. It cripples your life in a way.