Apparently the success of a popular, though not necessarily very good novel is to blame for Italy’s bridges being vandalised…
I know what you are talking about even without reading the article. It is sad, indeed. Until some decades ago, lovers wrote letters to each other. Now they can’t write any more, so the easiest thing they can do is to spoil an innocent, unlucky bridge. 
By the way, the fans of Moccia (the author of those sort-of books) are called mocciosi, which also means “snotty kids”.
It seems every book Moccia writes adds some hundred kilos of padlocks on Italian bridges… And his work is being translated into many languages, but unfortunately research has not yet developed a vaccine, so beware the Moccia syndrome! It can become a worldwide epidemic!