But it would be offset by the massive and recurring income from installing and maintaining the devices by a third party.

Let's see who the companies providing these services are owned by.

Like when ticket cameras in vans became a thing 25 years ago: 80% of the "ticket" went to the camera van company. I say "ticket" because in many US jurisdictions only a police officer can issue a ticket, so these were unenforceable as tickets.

States had to update their laws to add "civil fees" as a thing just for such cameras.