Venice likes the idea, and is contemplating doing it.
http://www.veneziatoday.it/cronaca/f...i-venezia.html
A few excerpts from the article:
"This is an idea to discourage ill-mannered tourists and impede rude behaviors that are prohibited by community norms."
"The mayor of Florence gave the order to wet the steps of sacred churches because tourists use them as places to sit and drink, and eat take out food."
"Good idea say Venetians. It might help get rid of tourists who carry sacks of food and eat on the steps as if it is their living room couch."
"People are keeping an eye on how it goes, with the possibility of copying this new Florentine system in Venice."
"With high season coming, episodes of ill-mannered behavior by tourists multiply, with them jumping into the canals, bicycling on the sidewalks, and having picnics everywhere."
"The mayor of Florence said that this in accordance with the requirements of managing a UNESCO site, where it's forbidden to camp out on church steps, eating and drinking. This will keep the space clean, and discourage tourists whom we'd otherwise have to fine."
"It is our task to respect the beauty and livability of the city. Who knows, maybe the mayor of Venice can push this."