Well - they might have been dumb enough to out themselves via social media. But if they didn’t, I’d be surprised if any of the librarians outed them.
The librarians I know take their code of conduct very seriously and part of that involves protecting the privacy of borrowers. They would never leak the names of scumbuckets like these, because they would never want anyone too think they would leak the names of ANY borrower. People need to be able to borrow from public libraries in the knowledge that they won’t be outed.
One of the Australian Privacy Principles is that data shouldn’t be kept if it no longer serves a useful purpose. I was involved in discussions about this at a university. The university had never deliberately deleted any data and was trying to work out a suitable length of time to keep non-essential data. They were talking in terms of decades. The library rep was aghast, pointing out that library borrowing records were deleted something like a week after the book was returned. (Alas, can’t remember the exact number of days. It was so set so they could tell if a student was re-borrowing a book that was in high demand.) The only exception was when overdue fines were involved. Students had something like 3 months to dispute fines, so borrowing record had to be kept that long for late returns.
In another case, I found an old public library card I hadn’t used for a few years due to no longer working near the library. I rang them to cancel the card. The librarian I spoke to proudly told me it had already been cancelled, because if a card isn’t used for 12 months they automatically delete the account to maintain privacy. I’m guessing the records of what I borrowed were culled much sooner, but 12 months after I returned the last book I borrowed from that library there was no data left showing that I had ever visited that library!
In case it’s not clear, I am mighty impressed by librarians. I was going to add a comment about there needing to be a story about a superhero librarian, but then I realised Barbara Gordon has already got it covered.