Phrased like that, it's indeed problematic. But you should keep in mind that speeding is
1. A safety hazard
2. Causes high noise pollution
3. Measurably increases air pollution
Under these circumstances I feel like a citizen driven enforcement for the law is not quite bad as you are portraying it. I would even call it apploudable, because they increase the quantity of life for everyone in their neighborhood.
Phrased like that, it's indeed problematic. But you should keep in mind that speeding is
1. A safety hazard
2. Causes high noise pollution
3. Measurably increases air pollution
Under these circumstances I feel like a citizen driven enforcement for the law is not quite bad as you are portraying it. I would even call it apploudable, because they increase the quantity of life for everyone in their neighborhood.