One time I parked in chinatown at 5:30 am on a Sunday in a spot that has free parking on Sunday.  At 2:00 pm when I left there was a protest, with a full band, bleachers,  and a dancing dragon around my car.  Along with a temporary no parking sign, and a ticket.  That sign was definitely not there in the morning, but I had no proof, so  I just paid it.<p>Interesting side note, I recently had an Uber driver who worked for the PPA.