Incompetent website administration.
I have shame of this but it isn't rare in the italian public administration services. I'm italian and NIVI is actually a private company that has a division that provides services to the town councils (E.M.O. --> European Municipality Outsourcing): one of this services is the notification of the fines to foreign people.
These are pages of some cities that are using that service: (Florence, english page)
http://www.comune.fi.it/export/sites/retecivica/comune_firen... /servizi_on_line/fine_payment_abroad.htm
(Rome, pdf, italian doc. )
https://www.google.it/url?sa=t&rct=j&q=&esrc=s&source=web&cd...
(Storo, italian page)
http://www.comune.storo.tn.it/delibere2007/d07_020.htm
etc.
I hope this info will be useful.
G.