There's an entire large segment of hip hop (underground/indie) that is probably more popular among suburban white kids (like myself) than black urban kids, and isn't about "being poor in a ghetto, being black, being gangster, going to prison, shooting cops, and murdering people", and, frankly, is not only much better than, but is in many ways directly opposed to the crap you seem to be referring to.
(its popularity does seem to be increasing among black youths, though, with new crossover acts like Odd Future)
Frankly, with the quality of the music in that subgenre, it's odd to me how anyone could not be drawn to it.
Putting that aside for the moment, though, I fancy myself a bit of a hip hop historian, so let me walk you through exactly how it was that White America came to be sold on hip hop...
First (and you may be too young to have experienced this), white kids my age (children of the 80s [young Gen Xers, old Millennials]) were brought into the hip hop fold when we were kids through total pop hop (garbage) that was decidedly not gangster, like MC Hammer and Vanilla Ice. The first album I ever bought (on cassette, mind you) was Please Hammer, Don't Hurt 'Em (my favorite song was "Pray", for those in the Hammer know *wink* *hammer dance*):
...and I would be lying if were to say that I did not at one time think Vanilla Ice was cool:
Then, moving on from the late 80s into the 90s, there was the undeniably strong Fresh Prince effect:
I mean, Will Smith was one of the hip hop stars of the 80s, and with this show he basically took over America. He presented a face so non-threatening and enjoyable that even grandmothers could say they really liked a rapper.
Moving on, growing up in California, when I was in middle and high school, the whole West Coast vs. East Coast feud drew people in as well. Regardless of what race or socioeconomic status you were, this was about geography! All of a sudden, you and the gangsters on your side of the country were on the same side against the gangsters on the other side of the country. Race didn't matter.
Then add in Eminem blowing up when I was, I dunno, a freshman in high school, as well as pop-heavy hip hop acts like Will Smith, or Run DMC collaborating with Aerosmith, other white hip hop acts like The Beastie Boys, or Naughty by Nature, and even other white acts that blended rock and hip hop, like *trying to remember these first douchebags' names* *can't remember it* whatever that band with Fred Durst was called and Linkin Park (who were blowing up, respectively, in the middle and end of my high school years), I mean, it's really not that difficult to see how white people got into hip hop. I mean, shit, the industry sure as shit wanted them to -- there's a shit ton of disposable income within that demographic -- and you can't tell me acts like Nelly, or even Dr. Dre's 'Chronic 2001', weren't aimed directly at suburban white kids. And if you could like Dre, why couldn't you like NWA, Eazy E, Ice Cube, Westside Connection, Snoop Dogg, 2Pac, and all kinds of other acts. I mean, shiit, I'm pretty sure my grandma could get down with a slick Nate Dogg hook. Who couldn't?
And that's mostly just West Coast shit.
(Oh, which reminds me... as the voice says at the beginning of the video: "He who controls the dance floor, controls the People." I mean, let's be real, 90s hip hop is fun as hell to dance to.)
Then there was East Coast shit, and, I mean, how fucking gangster, really, were Ma$e and Puff Daddy? Shit, Puff probably grew up wealthier than I did. I remember this shit coming out early when I was in high school, and there was nobody on the planet who didn't like this song. So now you've thrown Biggie into the mix, and he's more thug than Jay-Z ever was, so now you've got pretty much most of the mainstream hip hop establishment in bed with White America:
Then you've got weird ass acts like Wu Tang Clan, which is comprised solely of black dudes, but whose name (as well as many thematic elements in their music) is basically one giant shout-out to Asian/Japanese culture, and whose lyrics/songs, while gangster in a sense, were also so out there and weird that they managed to cross over (interestingly/oddly) all the way into a white skaterpunk demographic:
Another act who kinda fit that weird hop style, but catered to more mainstream tastes was Busta Rhymes, who, despite his relative unimportance and obscurity now, was actually a pretty major influence in pulling the suburban white kid into the hip hop scene:
Which reminds me (seeing as how he had a hit with Janet Jackson somewhere around my sophomore/junior year), that, honestly, Michael Jackson was a pretty big influence on white kids being open to getting into hip hop. As ridiculous as it may seem now, I remember as a kid having very strong post-racial views in no small part because of Michael Jackson, and, well, it's not hard to see how his stuff was not only aimed directly at white suburban kids (not exclusively, of course -- it was intended for everyone), but it was very specifically intended to stir post-racial views in the youth.
So, I mean, White America was well-lubed for the mass influx of hip hop that was to come in the 90s.
Then related genres, like R&B, kept the lube going, with acts like Janet Jackson, Whitney Houston, Mariah Carey, TLC, et al.
I mean, I specifically remember being in 5th or 6th grade, and wanting to rail the fuck out of Chili.
Add in R&B/hip-hop crossover acts like The Fugees and Outkast...
...and, I mean, how many more steps must one take to be willing to open up to hip hop?
Add on top of this the fact that white kids my age grew up idolizing sports heroes like Magic Johnson and Michael Jordan, Bo Jackson and Ken Griffey, Jr, and, I mean, when you want to grow up and "Be Like Mike", how much more does it take for you to want to "Be Like Pac"?
I could go on about the kind of hip hop I got into after the mainstream stuff started to suck, but, as for now, the defense rests.