They've even been caught putting them back up or re-enabling them in places where the contract has been canceled. How is that legal? I thought you had to be city-approved to install equipment like that. One would think that no contract = no approval?

Maybe they need to set up a "sting" operation at one of the disabled units and start makin' some arrests/fines for unapproved equipment installation/construction on public property? See if that changes some minds over at Flock about what they can and cannot get away with?