Perhaps it is not that they object to their presence, but to how they fear they will be used.
If someone is caught on a public place camera getting a quickie or taking a whiz, nothing is done about it because it doesn't necessarily violate a law if no one is there to be offended. However, if someone is there to be offended and complains, or has their wallet stolen or gets raped or beaten up or whatever, they can go back and find out what happened or at least show the victim's story to be true.
If highway cameras were to be used only to give evidence of who was at fault in an accident when someone filed a report (or even who tagged the overhead sign) rather than to catch someone who was driving at what was a reasonable speed that happened to exceed the state maximum or for proceding carefully through a stop sign that should have been made into a yield sign during certain hours, I might support them myself.
If highway cameras were only used by police in monitoring facilities to help us all get to where we had to be faster or to send help to stranded motorists or to help locate traffic problems or accidents quicker, I'd favor them myself.
If red light cameras were used as they should be in conjunction with slighly longer yellow lights (and possibly comenserately shorter all red times) such that only a real color blind dumbbutt would run a red light and get caught, I'd be in favor HUGELY of them.
Most of the time, when a decision is made to install a red light camera, it's because the format and timing of the light are bad to start off with. People proceed though lights when they don't think that they can reasonably stop before entering the intersection. If the yellow is too short, people get caught on the red. If they made the yellow sufficiently long, they wouldn't run it.
In my opinion, it would help both people and police a lot, if most interections with traffic signals had a line of distinctive marking (maybe a line of circular dots or a line of triple dots that looked something like a row of traffic signals) that showed where it was possible to make the light at something close to the speed limit. So you could see the "warning" line and the light. If you had them both in front of you, you should stop. If you saw that you had crossed the "warning" line and then the light turned yellow (and you weren't poking along) you would at least get into the intersection legally. Perhaps, we could even make two lines. One for "Mustn't stop at 10% under" and one for "Mustn't go at 10% over".
Of course, reasonable laws, such as non-freeway speed limits as they are in California, tend to foster respect for the law rather than encourage people to try to get away with violating them just because everyone else does. In California, speed limits other than 65 MPH or 70 MPH have to be justified by sound traffic engineering if they are to be enforceable and cops can't use RADAR to enforce limits that are set too low for political reasons (or for revenue generation). In other words, in theory at least, "just keeping up with reasonable traffic" is a defense against speeding tickets when the posted speed limit is below the state maximum. So, the municipalities in California try to set speed limits in town so as to facilitate the orderly flow of traffic and keep pedestrians from getting hit and not for revenue.
In a recent case of a red light camera, a municipality had to throw out a bunch of tickets because the yellow lights were too short. This is just a reminder to municipalities to "do it for safety, not for revenue".
