Cameras recording tour activity in malls, and on public roads has been the case since the 90s. Flock became a lightning rod of attention due to ICE, but they don't actually represent any change from the status quo.
At the end of the day, a camera in public can only record images of people in public. That does not and never did require a warrant.
The way to beat this isn't vandalism, it's getting them banned from every municipality and county in the country, while fighting at state levels for more bans.
It's also silly talk from kids online, just like "Don't vote, burn your local Wal-Mart" is only meant to impress other online children. The rest of us know that you'll neither vote, nor burn down the Wal-Mart.