This feels like a Cinderella story, where all possible good people are taken out and replaced with the bad stepmother and the fairy godmother replaced with a cool dog.
Their mentality is probably something along the lines of.
"It's a dump but it's our dump and our mess and your messing it up by adding your's!"
Their mentality is a dump. Pretty sure Popopoka is explicitly pointing that out with having Blind Girl's speech bubble being nice and clean (regardless of the state of her clothes), whereas her parents' are filthy and disgusting.
This feels like a Cinderella story, where all possible good people are taken out and replaced with the bad stepmother and the fairy godmother replaced with a cool dog.
Well, as we saw with blondie, the dog can straight up talk so there could be some magic stuff going on.