well that's because there's nothing like a good genocide to make an interesting character

but when you mention it... it does seem like they're milking the "i'm screwed up cause my family got slaughtered" thing a bit much.. (the only one i can think of (without thinking *too* much) is zabuza. it seems he was just born that way)

of course i guess it would be unappropriate to have a ninja who was messed up and went around killing because his uncle had sexually abused him when he was younger.. but still it would be cool to see some other angles.