And by rich, we're talking San Francisco expensive. This is not "upper middle class in Omaha" rich. This is money-coming-in-from-somewhere-else expensive. You are not moving to Venice and opening a diner, waiting tables, or opening a carpentry studio and selling chairs. You are definitely not selling sharpened pencils (http://www.artisanalpencilsharpening.com/index.html)

Not everybody who lives in Venice is rich, but it is rapidly becoming that way. There are a fair number of longtime residents who live modest lifestyles. But they're discovering that they can sell their houses for umpteen gazillion dollars, and thus this article.

It's kinda unfortunate, but Venice has basically been a museum of itself for centuries. It stopped being a world power and became a curiosity in the late 18th century. It took until now for tourism to ramp up from "part of the Grand Tour for British lordlings" to "cruise ships bringing tens of thousands of tourists per day".