Library Books

Ankit loves reading, and he occasionally borrows books from his elementary school library.

One day he is in the library, talking to the librarian.

Ankit: Do we need to pay for the books?
Librarian: No, you can borrow them for free one at a time.
Ankit: So, nobody has to pay for them?
Librarian: No. Only I have to pay for them when I buy them.
Ankit: You have to pay for them yourself? I thought you used tax dollars to pay for them.

Librarian doesn't know what to say.