The Question and Answer section for The Stranger is a great resource to ask questions, find answers, and discuss the novel.
From the text:
His first question was: Why had I sent my mother to an institution?
I replied that the reason was simple; I hadn’t enough money to see that she was properly looked after at home.
I will need to look further for other quotes regarding...
In my opinion, Mersault felt they were judging him because they'd never seen him before.... he wasn't there while his mother was alive, and yet, he was there for her burial.