In hunting down a problem for a customer earlier this week I found the source of the problem to be a saved search "Favorites" that had no criteria.  In effect it was saying to return ALL the records in the list as it had no filters.  

Yikes.  I wondered how many other saved searches had that same issue.  It turns out quite a few!

I have updated all my customers saved searches having this condition to include the following words:  

THIS FAVORITE WAS SAVED WITH NO CRITERIA - CONSIDER DELETING