What is the effect of the author's writing style (no quotation marks or separation of dialogue)? Why would the author create this effect for the reader?

When all is said and done, there is not all
that much difference between helping a blind man only to
rob him afterwards and looking after some tottering and
stammering old person with one eye on the inheritance. It
was only when he got close to the blind man's home that
the idea came to him quite naturally, precisely, one might
say, as if he had decided to buy a lottery ticket on catching
sight of a ticket-vendor, he had no hunch, he bought the
ticket to see what might come of it, resigned in advance to
whatever capricious fortune might bring, something or
nothing, others would say that he acted according to a
conditioned reflex of his personality. The sceptics, who are
many and stubborn, claim that, when it comes to human