The novel states that Sonny lived on the mall. But after Vito is shot, Clemenza knocks at the door of Sonny's kitchen, and it appears like an apartment somewhere in the city. If it was at the mall, why would Sonny draw a gun?
So, does the film change it for the sake of drama? Or do we have to assume that Sonny was so scared that he feared assassins on the mall?

BTW: Is it "at the mall" or "on the mall"?