Chrome extension publisher's extension count stats
Here are the extension count break down across 114,038 authors in Chrome Web Store. A publisher can use any name without verification from Chrome Web Store, so it is possible for a publisher to impersonate another publisher!
The vast majority of Chrome Web Store publishers have only 1 extension, but 716 (0.63%) publishers have 10+ extensions. 5 publishers even published 1000+ extensions - most of which are themes / new tabs.