For him, nothing has changed. He is more concerned with his daily routine - tomorrow he will have to return to work. Everybody was privileged. There were only privileged people like him. Meursault is responding to the Chaplain's attempt to believe in God and admit that he is wrong.
Existentialism stresses the importance of individual choice.
Meursault chooses not to accept God, he believes in nothing. Even though he believes nothing he still has the choice. He is the sum of his actions. Absurdity - Life for Meursault is often absurd. When life is absurd everything seems out of place and everyone seems to be happy and well adjusted, however the individual is not.