Why did the lorry driver find the destruction of the house humorous?

Part of what makes this story so challenging in terms of
its impact on the reader is the reaction of the truck driver to all that he is seeing.
 The truck driver is struck by the sheer surreal nature of that which is around him.  It
is so destructive that it almost shocks the sensibilities to a point where laughter is
evident.  The final paragraph of the story reveals this.  The driver laughs because he
recreates the entire situation.  Starting with "the sudden check of his lorry" and "the
crash of bricks falling."  There was "dignity" at one point, and then nothing.  The
driver does not mean to insult Mr. Thomas, as he does indicate his apologetic stance
towards everything.  Yet, he does clearly say that there is humor in the situation that
exists outside of the situation. In saying," there's nothing personal," the truck driver
gives a clear indication as to why he found the situation humorous.  The setting that
has emerged is one in which there is no personal connection.  There is nothing personal.
 There is merely situations, devoid of human emotion and affect.  It is in this
condition where humor emerges, almost creating a barrer between individuals and their
world and one another.  Through this, the truck driver laughs at the predicament of
another.