"unbanked" and "underbanked" are a great illustration of the way one can misapply terminology to create an artificially negative view. I would suggest that most who would be considered "un[der]banked" by the banking and commerce industries are quite happy with their status.

We should try not to proliferate terms that imply a negative accusation just because someone chooses to do or believe an innocent thing that's different from what some other people do, believe, or want others to do or believe (particularly the word's inventors).