They probably get a few cheaters. But they save a fortune on the cost of a full-time employee or maintaining 100 parking meters. And it’s a ton less work. I’m sure a deal with an independent tow truck company handles enforcement for them, for free.
There a are a few big lessons here:
1. 100% isn’t worth it. The cost of collecting every last cent may cost more than you get. Understand the marginal profit on each action.
2. ROI has 2 numbers. Want to improve ROI? Don’t get obsessed with increasing the R. Reduce the I.
3. Chill out. Stress and workload are real business factors we forget to measure. Can you get most of the upside with a fraction of the hassles?