there have been scandals about road cameras (speed, red light, etc.) in the past, because you are right, they're essentially just tax collection tools. in tens of cities, about 15 years ago, yellow lights were on for less than 3 seconds, even about just one second in a few places. now here they're talking about how 30 km/h should be the fastest you could go in cities. the alternative is often awful public transportation, either because vehicles catch fire, are late or dirty, they break, or simply don't show up. public service could also be inefficient or de facto inexistent in a few cities.