Maybe Because He's Not That Kind Of Guy Who Enjoys Looking At Naked Women. I Admire Guys Like Ichigo. Most Guys Now-A-Days Would Do Anything To See A Girl Naked.
It is also for comedic effect
I mean i use to be exactly like that my friends bother me with that stuff and i would say to stop because i had my pride to protect, but still not werth protecting pride when you could be liking a girl.