"Smells like a 1st Century Roman disinformation op to me."
I had a similar thought, but point the finger at the Jewish priest caste in Israel at that time; those with the most to lose. The New Testament speaks about how they tried to start disinformation at the time.
You do know that Joseph, Jesus, and Mary were extremely common names at that time. It wouldn't mean a whole lot finding families with those names, anyway.