The protesters in Detroit were talking about occupying vacant buildings, of which there are plenty to choose from here. Now I know why that was making me so uneasy, although if they stick to occupying vacant single houses, then it probably wouldn't come to that and could end positively, if they decided to purchase (or make a deal with a desperate city government) and rehab the houses. The problem would be if they took over a whole block, or a large abandoned apartment building or factory complex, of which there are also many around here.
Rehabing buildings is hard work, and these guys aren't exactly known for their work ethic. Purchasing the buildings and fixing them up also takes money, which they also don't have a lot of, or a lot of interest in earning. They'll happily squat in an abaondoned building, but anything beyond that is too much trouble for them.