It's wouldn't ever be legally equated to lynching if it's black on white crime. To many self hating white people have made so anyone that says different is labeled a racist and for some reason everyone is so afraid of that label they'll do anything to avoid it.
The reason poor people act like this is because they literally don't give a fuck. A lot of people are brought up with the mentality that they can't do any better and won't ever be able to do better, because no matter how well they do society won't accept them. In part they're right, society won't accept them, because they weren't brought up to be part of "the other peoples" society. They have no idea how to function in it so they lash out. Being mostly uneducated it tends to be more violent than an a way an educated person would lash out. Not that this excuses their behavior for randomly attacking people, but it kind of explains it.
I'm normally wearing dickies, chucks / adidas, tshirt and baseball cap. I've dressed like that for probably 2 decades and now I have enough money to live in a "nice" community if I wanted too, but I honestly don't share a lot in common with the people that live there. I didn't grow up going to good schools, living in a good neighborhood, their social circles, and I don't leave my house everyday at 7 and get home at 6. I have long hair and tattoos and since I don't look and behave like them they assume I'm selling drugs or doing something else illegal. The police bother me and people file complaints for shit they imagine. I don't want to change who I am to live there with out being harassed. If I walk into a Channel, Louis Vuitton, Gucci, etc store people literally walk away from me, because in their mind I shouldn't be there. I'm not dressed like them and they have stereotyped me with out even hearing a word that comes out of my mouth.
The poorer communities need positive male role models reintroduced. While people don't like to admit it we're animals and sometimes behave as such. Take for instance when young male elephants started raping and killing rhinos. This behavior started occurring, because a large number of adult male elephants were culled. So when the young male elephants started reaching adulthood there weren't any adult males to show them how to behave. Once they reintroduced the adult males the problem went away. While this alone won't be a complete fix, because of human nature, over time it will help a lot.
That being said anyone (or group) violently attacking people deserves what they get. I had a guy try to carjack me several years ago at knife point and it didn't work out to well for him. I took his knife away and cut him up with it pretty bad. If I would have had a gun his brains would have been all over the road.