Years ago I was walking down a street with a friend in Santa Cruz. There were parking meters on the street and a parking enforcement officer was behind us, issuing tickets for expired parking. My friend started putting coins into expired meters next to parked cars. The enforcement officer quickly drove up to us and yelled at my friend, telling him that he was breaking the law.
I wonder if city governments are going to try to outlaw Tixxii, an app designed to enable good samaritans to warn people that their car is about to get a ticket? It also allows them to let car owners know if another car hit their car while it was parked.