The only difference between this and having police officers sitting there and looking is this is much cheaper and more efficient.

Sure, but that's a huge problem, because the legal system wasn't actually designed for perfectly efficient enforcement. It is important that people be able to get away with breaking the law most of the time. If all of the tens of thousands of laws on the books were always enforced we would all be in prison and bankrupt from fines. Some laws are just bad too, and the way they get repealed is when enough people get away with breaking them for long enough to build political momentum for it.

Also, it isn't like they are going to stop at using scaled-up AI surveillance just to enforce seatbelt use and texting while driving, there is way too much potential for abuse with this sort of tech. For example if there are these sorts of cameras all over, networked together, anyone with access to them can track just about everything you are doing with no way to opt out. Even if you aren't doing anything wrong the feeling that you are always being watched is oppressive and has chilling effects.