Probably different in different places, but in many libraries I've been to, you often interface with student part time workers or the stereotypical ancient person who still lives in a previous age and is bitter about people being impolite.

But I'm always reading positive stuff about American public libraries that they are not really just about borrowing books, but free internet, photocopying, showers, some kind of free social program to help poor people with any information related stuff, like job search or government forms.