First, the bottom line: Submitting your email address to the [city-name] website will not result in an increase of spam sent to your email address.
Spam has become the bane of the Internet. As the ratio of email’s intelligence to noise rapidly approaches zero trust and confidence are being destroyed. Spam has dramatically changed the nature of interactive participation; people now shy away FROM entering their email address anywhere fearing an invasion of both their privacy and in-box. In a recent New York Time magazine section article titled Tangled Up in Spam James Gleick, author of the award-winning book Chaos, stated that spam messages account for the majority of all Internet email and cost bandwidth purveyors, such as your Internet Service Providers, billions of dollars every year.