Apparently, he is phobic about the odour food leaves behind on our hands, even after washing them. So he always eats only with a fork, spoon and knife.
While drinking in a bar, he forgoes the usual bowl of nuts, because he does not want to pick them with his hands and because other hands, who still carry the odour of food, would have picked the nuts, spreading the odour.
He also refuses to shake hands with people who he thinks will have the odour on them.