There are many Zope sites around the world. Although it is hard to find “pure” Zope website, build without any other framework. The most popular are: Plone, CMF and Silva. If we can consider also them, then the number increases exponentially. On zope.org we can find many examples of existing sites.
List of major Zope websites that have more than 1 line of Python code I’ve written. Some of them I’ve created, some only maintained or helped to develop.