The Sociology of Libraries, part 4

Whenever I say I work at a library, the standard response I get is, "oh, that must be very interesting". I usually agree, say how I enjoy it, and so on...then there's an awkward pause, and without fail, no matter who I'm talking to, will say something like "there was this one time when I had a fine at my local/university/state library, 'cause they said they couldn't find a book, but I knew I'd returned it, and then they wouldn't believe me, but I knew I'd returned it". Or something about disputed fines, or how they couldn't find what they want, and so on. I am curious as to why people feel the need to tell me arbitrary stories about their bad experiences of libraries particularly as they're always libraries I've never heard of, or definitely have no connection with whatsoever. If someone tells me they're a doctor, I don't tell them bad stories about going to the doctor, or how they didn't tell me what I wanted to hear. Why is it that people only tell me bad stories about libraries? Are libraries really that bad? It always strikes me as an odd response to their original statement that working in libraries is interesting. Why do libraries invite such criticisms? What is it about this career that people feel the need to comment on? The main thing that irritates me is that they're such arbitrary stories. If they actually meant something, I would be more patient in listening to them, but listening to complaints about problems with libraries which have nothing to do with me, and that usually occurred at least 1 year ago, tries my patience beyond belief. Particularly as it keeps happening more and more!