The average police officer in the Bay Area costs $200k with benefits. Can each police officer bring $200k worth of fines in per person? Moreover, what kind of a system will you create if you incentivize officers to pay their own salary through fines?
If you're saying the police is massively overfunded, yeah. Officers also already often face quotas in many places, so you already know the answer to that question.
But the better question is why would you need to have overpaid humans drive around in cars to catch speeding violations? In most of Europe you almost never get stopped by cops for traffic violations. Most speeding violations are caught by stationary radar traps, a machine can run the plates and send you the ticket by mail, including a pretty picture of the driver of the car if you want to dispute who drove it. Sometimes there are similar traps activated by passing a red light. It'll even tell you how the long the light had been red when you passed it.
The reason that doesn't happen in the US is privacy regulations and because generally speaking lower income areas are less pedestrian friendly than higher income areas, so lower income areas will probably have more speeding. Not saying I agree with these reasons but it is why the political calculus in the US exists.
