Years ago I got a ticket supposedly from Skokie Il for overtime parking. I've blown through there on I-94, but never stopped there. Sent the letter back, and didn't send any money either.
This is a new scam in bigger cities. Fake parking ticket is put on your car, you find it and it looks official. You know you shouldn't have the ticket, but if it's paid in 24 hours the fine is only $3, goes to $30 after 24 hours, then up from there. You figure [censored], it's easier to pay $3 than fight it, and happily scan the QR code, go to their website, and give them your credit card and all of the info they need to max it out.
Heard a different one this week, in regards to the Detroit Auto Show: instead of giving out thousands of $$ worth of brochures, they put a QR code on the display, and you can get all of the information. Scammers are printing their own QR code stickers, putting them over the ones on the display, and when you scan it and go to the site, it steals all of the info from your phone.