Yeah, the bailiff at my initial date explained that you don't actually have to come to court to plead not guilty. The new date is only a pre-trial hearing where you meet with the city attorney to discuss the case. If you can't cut a deal you'll go to trial, and that's where the cop has to show up. They have to pay the cop for his time in the courtroom (which may be overtime for him/her) as well as the usual overhead for prosecuting a stupid traffic ticket, so they'll offer you something just to avoid all that.
I got nailed on Lake Drive, right by Layton Ave. Yup, that's right, I got nailed RIGHT IN FRONT of the police station. I thought the speed limit was higher than it was, and that the cop shop was further north than it was