 The black and white photography is ultimately an homage to 70s and  80s US television airings of kung fu movies. Black and white (as  well as black and red), were used to conceal the shedding of blood  from television censors. Originally, no black and white photographic  effects were going to be used (and in the Japanese version none  are), but the MPAA demanded measures be taken to tone the scene  down. Tarantino merely used the old trick for its intended purpose,  rather than merely as an homage.