I wonder if this could be the page layout algorithm? You can read more about that here. This effectively goes after sites / pages and "downgrades the ranking of a web page with too many ads at the top or if the ads are deemed too distracting for users."
The problem might now not be to do with links, but could be something else - or a combination. The Wix banner doesn't appears to be no-followed either.
Bluehost at the bottom left (image link) also doesn't appear to be no-followed.
-Andy