Libraries are like houses of worship: Whether or not you use them yourself, it's important to know that they are there. In many ways they define a society and the values of that society. Librarians to me are the keepers of the flame of knowledge. When I was growing up, the librarian in my local library looked like a meek little old lady, but after you spent some time with her, you realized she was Athena with a sword, a wise and wonderful repository of wisdom.
Personally, I felt pretty safe. Librarians are like priests. You can tell them you want information on just about any subject and they never look at you weird. It's like a rule or something. I figured even in a small town like this, my question wouldn't be the strangest one the librarian had heard. I didn't know if librarians had any sort of official privacy code, but I was counting on confidence. They're not big talkers. It comes from being forced to be quiet all the time.