what is the purpose of including empty beans.xml in CDI implemenations projects?

CDI needs to scan all the classes of a bean archive at start-up and fire a bunch of events because almost any class is automatically a managed bean (read more here), even if it doesn't have any annotations.

This would incur quite a bit of overhead, especially for jar files that are not meant to have any beans, and it is therefore beneficial to explicitly indicate which bean archives should be scanned by including the beans.xml.