Libraries are founded to share knowledge among the reader base, therefore they should be open for all in the society. Specially this is the case for most of the public libraries, where anyone can go and check-out books quite easily. So, why should there be an obstacle to join a Library.
For last couple of months, we have received many requests from our librarians about an easier option to bring members / patrons on-board. Consider a library with hundreds of members, it was a sheer pain for our librarians to bring the member base into their online library and keep track of their invites.