Honestly I only watched the start of the film, so the movie may not be about the salesman.
I remember it started with a teacher/couch talking about marketing( i think it was a darky scene). He was telling the studients that there was a person that manage to sell him a basketball t-shirt, without liking basketball at all, I remember very clearly that line. And then the movie makes a transition to that salesman, then start talking about sales things directly to you. Also he was at mall, (and maybe he was the boss there?).
