This is not a racial problem; it's a socio-economic one. Middle and upper class blacks or any other minority race generally don't exhibit the behavior you're describing any more than middle or upper class whites do. The problem is that when it comes to racial minorities far fewer of them, with the exception of Asians, are on the upper end of the socio-economic scale and hence as a percentage of their demographic are more prone to this type of behavior, but poor whites behave no differently. As a landlord, I've been burned by white redneck trash equally as much as I've been burned by black ghetto trash. You'll notice you rarely see Asian running around gangbanging in the ghetto because they're the most well off and educated demographic in the country, black and Hispanics, not so much, and that is why as a percentage of their race this behavior is more prevalent.
People are a product of their environment at the end of the day. I train at a martial arts gym where Hispanics are the majority and the rest of the group there is made up mostly of whites, blacks, and Asians. Nobody there, adults or kid, behaves the way you're describing. We're all a family and would go to bat for each other because with that training also comes discipline and respect for not just each other, but everyone outside those walls.
Your experiences are simply a result of being in the wrong environments.