[refurb]

Because they are under the (mostly correct assumption) that poorer neighborhoods (which are often, but not exclusively, minority neighborhoods) have lower police presence.

And also that radical hippies tend not to have a lot of money, so it's not unusual for them to live in low income neighborhoods (i.e. some members likely lived there anyways).

[doktrin]

This is an infamous and reasonably well documented small group of people. You don’t need to speculate about their socioeconomic status because we know who they were and can count them on two hands.

TL;DR none of what you said remotely applies. They were middle-upper-class with access to resources and lived in Berkeley before moving to a notorious Concord safehouse in August ‘73, about 3 months before anything in this story takes place.