That's their parents' home, no?

The US middle class is shrinking. And it's always dangerous to have lots of young men with no prospects. With no future worth living into.

But seriously, mass shootings are just a sideshow. It's the political implications that are truly frightening.

>That's their parents' home, no?

Are there a lot of parents that won't allow their kin to live with them when the only other option is homelessness?

Kicking them out might not mean instant homelessness, they can get a job before leaving the house, crash on a friends couch.

However they're at a much greater risk of becoming homeless.

yes

It's not necessarily about whether they are/were objectively poor. I believe, (part of) it is about the perception that others/outsiders are getting an unfair advantage at the cost of the tribe the shooter identifies with.