I think you are underestimating the ignorance of public. Take poll of people. Most won't know that you have to wait years to get a trial. Most won't know that the majority of cases never make it to trial and are resolved plea deals (some of which are innocent people pleading guilty to avoid sitting in jail because they can't afford bail). Most won't know their civil rights (ask them about Brady vs MD, Miranda, the 4th ammendment, etc). How many do you think understand jury nullification?
These people fund the system through their taxes. They sit on juries. They elect people who commit abuses and allow abuses to happen. Even the ones who have been a victim of the system may not know it, the extent that it is common, or the other parts of the system they have not experienced.
For example, you could have a summary offense filed against you and the officer might amend the charge at the trial. If you aren't given a continuance, then it could violate your rights. If the change was made because the officer made a mistake and you didn't realize/understand it, if he will possible lie to the judge and say the change was for leniency (concealment of exculpatory evidence). At the very least, you wouldn't witness prison conditions for most summary offenses. For reference, approximately 8% of the population has been convicted of a felony and less than half of them have served time in prison. So the people with firsthand prison experience will be quite low (guessing less than 10%, but couldn't find those numbers).