Custom PiPass database

[vSanjo]

What are the implications of creating a custom database and controlling who is added/removed from the StreetPass roster?

e.g: A user 'A' is given access to the PiPass network and 'sends' their StreetPass. It's stored. Another user 'B' is given access and soon-after receives A's data. User 'C' comes along days later and receives 'A' and 'B'.

From my understanding, PiPass uses pre-created list of StreetPass users stored on Nintendo's end, correct? Is there a way to bypass that and store them locally?