In the DFW area, the town of Southlake, between Dallas and Ft Worth, used to have a cop that would nail you, keeping the speed differential just under the level that would impact your license. Just a money mill. And this was a very high dollar home community. Locals never got a ticket.
State passed laws shutting down these ticket mills, setting a max that tickets could be of their budget, mandating the bulk would go,to the state, etc.
They did the same thing in Georgia with the “Ludowici Law’. Locals could not give a ticket for less than ten miles over and the highway patrol generally would not.
I once visited a friend who was locked up in Ludowici. It was not even up to the standards of Mayberry. Two decrepit cells with a master padlock to hold them shut.
Macks Creek Missouri did the same thing in Missouri passed a law limiting the revenues derived from speeding tickets. They ended up writing a lot of tickets for illegal Lane usage and other garbage like that. Eventually they went broke after being raided by the state police.