They do more than take license plate data.

Hackers Got Inside a Flock Camera. Its Data Shows How the System Really Works [0]

Hackers Stole Flock’s Camera Software, Revealing How the Company Tracks Cars and People [1]

Flock ALPR camera, Distributed Denial of Secrets [2]

[0] https://www.wired.com/story/hackers-flock-camera-data-shows-...

[1] https://www.404media.co/hackers-stole-flocks-camera-software...

https://archive.ph/gQoMs

[2] https://ddosecrets.org/article/flock-alpr-camera

Honestly, Flock should be dropped in general.

But someone will be able to get vehicle data out of them was just a matter of time.

Such systems are never great. Even when you ignore the obvious reasons on why not to do that, security is just the last nail in the coffin. Now just imagine what bad actors can do with that data. They now helped the people they are trying to avoid and they always will