Except realistically you've never going to accurately gauge exactly which books taxpayers do and don't agree should be purchased with 'their' dollars, nor are i

Except realistically you've never going to accurately gauge exactly which books taxpayers do and don't agree should be purchased with 'their' dollars, nor are individual vote counts going to determine the choice of books that public libraries choose to stock. If the public happen to vote for a party that once in government then decides particular books should be restricted in public availability, it's still censorship. I'd like to think there were basic constitutional principles in place that determined on what grounds such censorship is and isn't genuinely in the interest of sustaining a healthy liberal democracy.