Have you ever heard of the gay panic defense? Hate crime legislation, I think, might do something to reduce the effectiveness of such legal defenses. Re: awareness, the law also serves to remind everyone else that this sort of attitude towards GLBTs is unacceptable; lots of people would agree with the beating-someone-up-cos-he's-gay, even if they didn't actually do it themselves. It's a kick to the collective of haters. And it's really useful to have a specific law that one can cite in arguments with other people--"look, the govt thinks this isn't right, it's not like we're some strange minority of people calling for equal rights". It's all about changing attitudes and people's minds.