Why do people that are Into rap and hip-hop even want a high-end audio system

I think that anything you listen to deserves high fidelity reproduction, whether you consider it music or not. You'll enjoy it more with a good system. That's my opinion.

That said, if the content has no melody, then it's not music. Melody is the substance of music; no melody, no music. Simple as that. If you want to get technical, harmony and rhythm are outgrowths of the melody, which is the core. You can have only chords and a repetitious drum beat, but that's like having an empty box with nice wrapping paper.  

Of course, you could call anything you want music. That's in the realm of opinion. I can call my cat a dog, but that doesn't make my feline a canine. I hope we can agree that you wouldn't call a building with no foundation, no roof, crooked walls and a few doors and windows a good house. It may be where you live, and you have every right to love it as your home, but that doesn't make it a sound structure. Strumming chords is not a song; repeating a rhythm on drums is not music. That's not racist, rigid, opinionated or narrow-minded. It's just fact. And it still allows you to enjoy someone speaking rhythmically over an ostinato rhythm in high fidelity.

It's still an unfair presumption.  It's saying, "I know what you're thinking and what's in your heart."  It's very unfair.  I was largely raised by a black lady who I loved.  I worked under black men and I worked side by side with black boys.  I formed and played in a band with a black friend when I was in high school.   I have spent my adult life playing a lot of black music, listening to a lot of black music and supporting political candidates who I think cares about minority causes.  I would never support one who I thought did not. 
I grew up in the old south.  I knew men, and sadly, kids who thought black people were inferior.  You know the story, you've seen it in movies and tv all your life and maybe you grew up with it, too.  I'll not have you putting me in with those miserable people I knew long ago.  If you do you are making a big mistake.  Excuse me if I don't sit here and take this quietly.

@onhwy61 Thank you for articulately stating what I was flailing around trying to say.

aolmrd1241: I enjoy my Everlast "Eat At Whitey's" lp from time to time. FWIW: I believe the first song with rap to reach #1 was Blondie's "Rapture".

Listen to Mos Def, Black On Both Sides on a good system. Outstanding album.