I think that the courts ruled that if a burg received a disproportionate amount of revenue from traffic ticket, that they were not truly an incorporated town and had to give up their town charter. Don’t remember where I read but it was maybe 10 years ago or more.
Trying to find my article link I did see other articles pertaining to the “speed trap” laws that looked like they went back to the 1970s to try to stop some of these towns. Especially common in the south.
Back in the mid 80’s I got a ticket for doing 32 in a 30 in Chubby Checker’s home town! (S. Carolina iirc?) Out of state plates....