Anyone else ever share (2) Duplicate email addresses with another User?

The Internet has two Users, me and another guy with the same name in a different state who have duplicate email addresses.  While talking to 6 differnt user help people in Xfinity who say "That, of course, is impossible". -- LifeLock consistantly says so, as does 3 other Search sites I found within 20 minutes of searching:  xlec.com -- a public data search co, Clustrmaps.com, a R/E and Data search site, and InfoTracer, a Revere email search site which shows the other guy, but not me!   -- 

I realize the Xfinity DB will not allow two dupes -- but no one in Xfinity Customer Assurance has yet to suggest how this can occur!